Validate example configs with CircleCI

Runs in parallel to TravisCI and runs *much* faster on same jobs.  Finishes all examples configs in <8 min on cache hit; <10 min on cache miss.  Cache miss is triggered on platformio.ini change. I'd suggest move to it entirely, but it is limited to just 1500 min of runtime per month and it isn't clear yet how much Marlin would need so suggest we implement in parallel like this, then observe.  If the example builds don't catch issues, and 1500 min turns out to be plenty, we can switch to implimenting standard arsenal of tests in CircleCI and ditch TravisCI to gain speed improvement (although I do like seeing the varied Travis avatars staring at me ;).

I agree that hand-crafted tests would be better, but until we have that, this can't hurt.

After merging, you'll need to add Marlin project to CircleCI at: https://circleci.com
Example results at: https://github.com/fiveangle/Marlin/commits/bf-circleci_config

.circleci/config.yml

@@ -0,0 +1,289 @@
+# Python CircleCI 2.0 configuration file
+#
+# Check https://circleci.com/docs/2.0/language-python/ for more details
+#
+version: 2
+jobs:
+  build:
+    docker:
+      # specify the version you desire here
+      # use `-browsers` prefix for selenium tests, e.g. `3.6.1-browsers`
+      - image: circleci/python:2.7.13
+
+      # Specify service dependencies here if necessary
+      # CircleCI maintains a library of pre-built images
+      # documented at https://circleci.com/docs/2.0/circleci-images/
+      # - image: circleci/postgres:9.4
+    environment:
+      TEST_PLATFORM: "-e megaatmega2560"
+
+    working_directory: ~/Marlin
+
+    steps:
+      - checkout
+
+      - restore_cache:
+          paths:
+          - ~/.platformio
+          - ~/Marlin/.piolibdeps
+          keys:
+          - v1-dependencies-{{ checksum "~/Marlin/platformio.ini" }}
+          # fallback to using the latest cache if no exact match is found
+          - v1-dependencies-
+
+      - run:
+          name: install dependencies
+          command: |
+            sudo pip install -U platformio
+
+      # run tests!
+      - run:
+          name: run tests
+          command: |
+            #
+            #
+            # Fetch the tag information for the current branch
+            ls -la
+            git fetch origin --tags
+            #
+            # Publish the buildroot script folder
+            chmod +x buildroot/bin/*
+            export PATH=`pwd`/buildroot/bin/:${PATH}
+
+            # Generate custom version include
+            generate_version_header_for_marlin ./Marlin/src/inc
+            cat ./Marlin/src/inc/_Version.h
+            #
+            # Backup pins_RAMPS.h
+            #
+            cp Marlin/src/pins/pins_RAMPS.h Marlin/src/pins/pins_RAMPS.h.backup
+            #
+
+            #################################
+            # Build all sample configurations
+            #################################
+
+            echo testing megaatmega2560 targets...
+            export TEST_PLATFORM="-e megaatmega2560"
+            restore_configs
+            echo use_example_configs adafruit/ST7565
+            use_example_configs adafruit/ST7565
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs BQ/Hephestos
+            use_example_configs BQ/Hephestos
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs BQ/Hephestos_2
+            use_example_configs BQ/Hephestos_2
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs BQ/WITBOX
+            use_example_configs BQ/WITBOX
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs AliExpress/CL-260
+            use_example_configs AliExpress/CL-260
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Cartesio
+            use_example_configs Cartesio
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs delta/FLSUN/auto_calibrate
+            use_example_configs delta/FLSUN/auto_calibrate
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs delta/FLSUN/kossel_mini
+            use_example_configs delta/FLSUN/kossel_mini
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs delta/generic
+            use_example_configs delta/generic
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs delta/kossel_mini
+            use_example_configs delta/kossel_mini
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs delta/kossel_xl
+            use_example_configs delta/kossel_xl
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Felix
+            use_example_configs Felix
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Felix/DUAL
+            use_example_configs Felix/DUAL
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs gCreate/gMax1.5+
+            use_example_configs gCreate/gMax1.5+
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Geeetech/GT2560
+            use_example_configs Geeetech/GT2560
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Geeetech/I3_Pro_X-GT2560
+            use_example_configs Geeetech/I3_Pro_X-GT2560
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Infitary/i3-M508
+            use_example_configs Infitary/i3-M508
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            #
+            # Disabled due to compile failure on E0_AUTO_FAN_PIN PB8
+            #
+            #  use_example_configs Malyan/M200
+            #  build_marlin_pio ./ ${TEST_PLATFORM}
+            #  restore_configs
+            echo use_example_configs Micromake/C1/basic
+            use_example_configs Micromake/C1/basic
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Micromake/C1/enhanced
+            use_example_configs Micromake/C1/enhanced
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs RepRapWorld/Megatronics
+            use_example_configs RepRapWorld/Megatronics
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs RigidBot
+            use_example_configs RigidBot
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs SCARA
+            use_example_configs SCARA
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Velleman/K8200
+            use_example_configs Velleman/K8200
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Velleman/K8400/Dual-head
+            use_example_configs Velleman/K8400/Dual-head
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Velleman/K8400
+            use_example_configs Velleman/K8400
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Wanhao/Duplicator6
+            use_example_configs Wanhao/Duplicator6
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            #
+            # Disabled due to compile failure on https://github.com/stawel/SlowSoftI2CMaster
+            #
+            #  - Requires https://github.com/stawel/SlowSoftI2CMaster
+            #  restore_configs
+            #  use_example_configs wt150
+            #  build_marlin_pio ./ ${TEST_PLATFORM}
+
+
+            echo testing anet10 targets...
+            export TEST_PLATFORM="-e anet10"
+            restore_configs
+            echo use_example_configs Anet/A6
+            use_example_configs Anet/A6
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Anet/A8
+            use_example_configs Anet/A8
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Creality/CR-10
+            use_example_configs Creality/CR-10
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Malyan/M150
+            use_example_configs Malyan/M150
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Sanguinololu
+            use_example_configs Sanguinololu
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs TinyBoy2
+            use_example_configs TinyBoy2
+            build_marlin_pio ./ ${TEST_PLATFORM}
+
+
+            echo testing rambo targets...
+            export TEST_PLATFORM="-e rambo"
+            restore_configs
+            echo use_example_configs AlephObjects/TAZ4
+            use_example_configs AlephObjects/TAZ4
+            build_marlin_pio ./ ${TEST_PLATFORM}
+
+
+            echo testing teensy20 targets...
+            export TEST_PLATFORM="-e teensy20"
+            #
+            # Disabled due to Z_MIN_PIN related compile failure
+            #
+            #  restore_configs
+            #  use_example_configs delta/kossel_pro
+            #  build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs makibox
+            use_example_configs makibox
+            build_marlin_pio ./ ${TEST_PLATFORM}
+
+
+            echo testing sanguino_atmega644p targets...
+            export TEST_PLATFORM="-e sanguino_atmega644p"
+            restore_configs
+            echo use_example_configs tvrrug/Round2
+            use_example_configs tvrrug/Round2
+            build_marlin_pio ./ ${TEST_PLATFORM}
+
+
+            echo testing LPC1768 targets...
+            export TEST_PLATFORM="-e LPC1768"
+            restore_configs
+            echo use_example_configs FolgerTech/i3-2020
+            use_example_configs FolgerTech/i3-2020
+            build_marlin_pio ./ ${TEST_PLATFORM}
+            restore_configs
+            echo use_example_configs Mks/Sbase
+            use_example_configs Mks/Sbase
+            build_marlin_pio ./ ${TEST_PLATFORM}
+
+            #
+            # Disabled due to numerous compile failures
+            #
+            #  echo testing STM32F1 targets...
+            #  export TEST_PLATFORM="-e STM32F1"
+            #  restore_configs
+            #  use_example_configs STM32F10
+            #  build_marlin_pio ./ ${TEST_PLATFORM}
+            #  restore_configs
+            #  use_example_configs stm32f103ret6
+            #  build_marlin_pio ./ ${TEST_PLATFORM}
+
+
+            #
+            # Disabled due do pin related compile failures
+            #
+            #  echo testing DUE targets...
+            #  export TEST_PLATFORM="-e DUE"
+            #  restore_configs
+            #  use_example_configs UltiMachine/Archim2
+            #  build_marlin_pio ./ ${TEST_PLATFORM}
+
+            #
+            # Remove temp files from dependencies tree prior to caching
+            rm -rf ~/Marlin/.piolibdeps/_tmp_*
+
+
+
+      - save_cache:
+          paths:
+          - ~/.platformio
+          - ~/Marlin/.piolibdeps
+          key: v1-dependencies-{{ checksum "~/Marlin/platformio.ini" }}
+