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

Some users may prefer to hide the position updates on the `LIGHTWEIGHT_UI` altogether. This leads to an even less cluttered display (it also saves on SPI traffic and one byte of RAM).

Some probes don't work near the edges of the bed. This change promotes MIN_PROBE_EDGE to a general setting that applies to all probing functions.

Some "fix-mounted" probes need manual stowing. And after probing some may prefer to raise or lower the nozzle. This restores an old option but tailors it to allow raise or lower as preferred.

* SD Status auto-report feature
Feature Request #9751

From #7314 by @MrAmericanMike

Fix #9208

Implemented for LPC1768.

- The status screen uses the ST7920 character generator to greatly
  reduce SPI traffic and MCU load when updating the status screen.

- Has been tested with the RepRapDiscount Full Graphics Smart Controller
  but should work with any LCD that uses an ST7920 or fully compatible
  controller.

- The status screen uses the ST7920 character generator to greatly
  reduce SPI traffic and MCU load when updating the status screen.

- Has been tested with the RepRapDiscount Full Graphics Smart Controller
  but should work with any LCD that uses an ST7920 or fully compatible
  controller.