* Make ExtUI respect MAXTEMP limits
  - Temperatures are now clamped by MAXTEMP limits rather than arbitrary values.
* Speed up USB init, add status
  - Speed up USB initialization
  - Show status message if init failed
* Enable status messages for EXTENSIBLE_UI
* Adjust max limit to MAX_TEMP - 15
* Misc. tweaks to formatting, const, etc.

* Add traceback after watchdog timeout

Add the cpability to perform a traceback following a watchdog timeout.

* Enhanced hardware SPI

Allow use of either SSP0 or SSP1.
Ensure that no data is left in I/O buffers after calls to enable sharing of SSP hardware.

* Make flash emulation of eeprom the default

Make use of flash for eeprom storage the default. This means that usage of eeprom will not cause USB drive mount/unmount operations.

* Allow sharing of SD card

SD card I/O operations from the USB stack take place in idle loop, rather than at interrupt time. Allowing sharing of the SPI bus.

New configuration options to allow usage of the SD card to be specified.

* Fix problem with hardware SPI pins

Framework and build platform now located at https://github.com/p3p/pio-framework-arduino-lpc176x and https://github.com/p3p/pio-nxplpc-arduino-lpc176x respectively

fix mkssbase leds

move hardware serial

remove hardware/software serial

Hardware Serial extraction

HardwareSerial ISRs

fix disabled serial2 causing Serial object to link

move usb devices out to framework

separate out adc/pwm peripheral function from hal.cpp

fix includes

remove unused pwm init

move adc

HAL header update

templated filtered adc

LPC1769 platform