Use "Tn S1" to change tools without moving

Use linear feedrate in gcode_T, not volumetric

Custom Splash Screen

Follow-up the PR #3676(Advance extrusion algorithm – LIN_ADVANCE)

・Update forgotten example configurations

Custom Splash Screen for full graphic displays.

Too complicated for the hitachis without knowing what exactly to display.

On top of #4032
Realisation of an idea from #3996

Fix broken DISABLE_HEATER macro

Parse M905 args in Marlin_main.cpp

Patch LIN_ADVANCE to use code_value_float

Show bootscreen later

Advance extrusion algorithm – LIN_ADVANCE

Update to language_it.h

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.

update to latest rcbugfix

Fix Travis test for FILAMENTCHANGEENABLE

Fix manual move for multiple extruders

Add macros to move servos

No need to check ULTIPANEL with DOGLCD

Heal the watchdog

Clarify names of prepare_move functions

Wrap all items depending on ULTIPANEL

Improves travis buildroot regexp

  manage_manual_move(); -> ULTIPANEL

Closes #3999: Compilation error with BEEPER_PIN -1

Makr the call of   `manage_manual_move() ` depandent of `ULTIPANEL`

Rename some vars to clarify their relationship to acceleration