- `pins_BIQU_B300_V1.0.h` defines pins for B300, as found in the BIQU Thunder 3D printer.
- `pins_BIQU_SKR_V1.1.h` defines pins for bigtree/BIQU SKR V1.1 motherboard.

Implement initial support for MKS Robin (STM32F103ZET6) board.
Custom build script is used to generate encrypted firmware compatible with original MSK Robin bootloader (i.e. safe firmware update from SD card and possibility to go back to original close-source firmware).

* Add Formbot Raptor2 board
* Add Raise3D Rumba board

* Apply #pragma once in headers
* Adjust some thermistors formatting
* Misc cleanup and formatting

* Add Formbot Raptor board

Co-Authored-By: InsanityAutomation <insanityautomation@users.noreply.github.com>

* Add a second Z probe Z offset

Co-Authored-By: InsanityAutomation <insanityautomation@users.noreply.github.com>

* Modify method to utilize live adjustment of hotend z offset

Should probably move config option to babystepping and rename as it may now apply to all multiextruder systems

* Move config item and catchup other code to current method

Indeed the HAL does not need to be mucked around with to expose ATmega2560 pins not available as numbers on the MEGA board, I'll need to update the wiki with that tidbit and a reference to the pin-mapping comment in `fastio_1280.h`.

- Ordering and match classification between `boards.h` and `pins.h`
- Check `pins.h` environments

STM32 ARM Cortex-M3 boards were listed as M4

* Add BOARD_MKS_BASE_15 with digital micro-stepping
* Rename MKS_13 to MKS_GEN_13

http://reprap.org/wiki/EinsyRetro

- Assign 243 (like EFB) as Ender-4/CR-8 board ID
- Add to `Makefile`
- Add to `pins.h`

Followup to #9008

- Don't define micro-stepping pins for boards that lack them.
- Allow setting of 128 microsteps with `M350`.