[2.0.x] Fix UBL compilation warnings

[2.0.x] add Due PINS_DEBUG support & misc improvements (replaces PR #8990)

[2.0.x] lcd_contrast type mismatch work around

[2.0.x] LPC1768 - PWM for any pin (replaces PR #8991)

Formatting tweaks

correct array initialization & remove test code

Based on #9008

Fix #8901

[2.0.x] Synchronize configs with 1.1.x

[2.0.x] SLIM_LCD_MENUS option

[2.0.x] Improve SW SPI for DUE a bit more

Now the USB MSD can transfer at 750k/s. Previously, it was 500k/s. I think this is the maximum achievable speed using Sw SPI.

[2.0.x] ultralcd.cpp: Better no_reentry, use in queuing G-code

[2.0.x] fix include in pins_RAMPS_FD_V2.h

[2.0.x] Display up to 3 extruders on char LCD

…and show bed level indicator at the position of the [H] icon, when a heated bed exists.

[2.0.x] DUE - update for Reprap Discount Full Graphic Smart Controller

[2.0.x] Multi extruder support for M600 / LCD

[2.0.x] No sub-menu if NO_VOLUMETRICS

For parity with #8911

[2.0.x] Fixes for G29, esp. 3POINT

[2.0.x] //Actions on Pause / Resume (M600, M125, etc.)