No way to fit Marlin into 32K.

Fixed a couple defines that were not changed or commented out.

language.h: update documentation for LANGUAGE_INCLUDE

@thinkyhead What do you think? I think there should be a warning like
this.

Minor wording correction.

Now ending in an endless loop.
Tidy up the output format.
We now get:
ERRORTEXT ", system stopped! Heater_ID: " HEATERID

Where ERRORTEXT can be:
"Heating failed"
"Thermal Runaway"
"MAXTEMP triggered"
"MINTEMP triggered"
and soon
"Thermal Jump"

HEATERID can be
0, 1, 2 ,3 , "bed"

This messages are always followed by the common:
"Printer stopped due to errors. Fix the error and use M999 to restart. (Temperature is reset. Set it after restarting)"

- Use a global pointer for the current sanitized command
- Pre-sanitize the current command to bypass `N` and nullify `*`,
removing the need for handlers to bypass, ignore, or nullify these
parts, and reducing overhead for `code_seen`, etc.
- Pre-skip leading whitespace.
- Only look for G, M, T codes at the start of the command.
- Verify that G, M, T codes are followed by command codes.

Moved SDCARDDETECTINVERTED and SDSLOW to Conditionals.h.
Added U8GLIB_LM6059_AF to define display specific actions.
Added reminder to compile in u8glib

to make it better findable.

Rename of define to avoid confusion between the controller and the
display which had similar names.

Fixes for some code formatting changes and commenting out the
ADAFRUIT_ST7565 define that was left defined.

Added support for new display type

- Also show 2 digits past decimal for Z on DOGM

- For better encapsulation add inlines for each prepare_move type
- Move controllerFan vars inside the function as statics
- Some formatting cleanup
- Rename `ClearToSend` as `ok_to_send`