As suggested in
https://github.com/MarlinFirmware/Marlin/issues/5570#issuecomment-283059
065

Also add a hotend indicator to the heating message displayed on the lcd status line.

Init display and show bootscreen later, but init display in `kill()`
to init outputs before the bootscreen delays but being able to display
kill errors.

Based on MarlinFirmware/MarlinDev#200 from @eboston

This is the easiest way to make button pin testing consistent without
renaming all the button pins. Just make a macro especially for testing
if button pins are set, since they are named consistently in the pins
files.

Following up on #3231

Alternative fix to #3149

Fix status LEDs update when reinitializing the display

By using the regular update function during init.

Fixing #2683

According to #123 negative values for XY at or below -100 are displaying incorrectly, dropping the first digit. Deltas can easily have XY values in this range. This PR adds a function to display floats/ints formatted like `_123`, `-123`, `_-12`, or `__-1` as appropriate and applies it to the XY coordinates on Hitachi displays. It also moves the Z value to the right to be consistent with the XY formatting.

Keep "astyled" reformatting

Apply `ENABLED` / `DISABLED` macros to LCD-related files.

at least the lcd independent part from Marlin_main.cpp.

by:
Moving HAS_LCD_BUZZ macro to Coditionals.h
Renaming HAS_LCD_BUZZ to HAS_BUZZER to make clear is has nothing to do with the lcd.
Removing the ULTRALCD condition.

Moving declaration of lcd_buzz() out of the ULTRA_LCD block in ultralcd.h
Moving definition of lcd_buzz() out of the ULTIPANEL block in ultralcd.cpp
Renaming lcd_buzz() to buzz() to make clear is has nothing to do with the lcd.

All buzzing code is now only dependent on the existence of a BEEPER-pin or the definition of a LCD_USE_I2C_BUZZER.

To do: Check the conditions for the BEEPER-pin in all pin-files.

- Also move audio feedback into the command
- Added shorthand for `lcd_buzz` availability