Deltabot settings and configuration adjustments.
Use X/Y/Z_MAX_PIN instead of X/Y/Z_MIN_PIN for top endstops on deltabot.
Enable QUICK_HOME for deltabot.
Add realtime delta geometry in Marlin_main.cpp.
Fix typo in MANUAL_HOME_POSITION (plural S missing) and reduce BLOCK_BUFFER_SIZE because 64 wasn't working for some reason.
Merged updates from Marlin_v1.
Fix home_all_axis to make QUICK_HOME work with Repetier-Host which sends G28 X0 Y0 Z0 instead of G28. Thanks to Matt Schoenholz for reporting this issue.
Fix typo (# missing before define).
{X,Y,Z}_{MIN,MAX}_POS are actually in Gcode coordinates.
Disable is now multi extruder compatible. M84 got a T option.
PID now per extruder. Fixed typo
Implement automatic extruder/cold-end fan control based on temperature

This change allows fan outputs to automatically turn on/off when the
associated nozzle temperature of an extruder is above/below a threshold
temperature.
Multiple extruders can be assigned to the same pin in which case the fan
will turn on when any selected extruder is above the threshold.
It also makes the M42 command compatible with the M106/M107 command.
The majority of the logic in this change will be evaluated by the
compiler at build time (i.e, low code space requirements).
Further reduce code by using precompiler logic
Number of extruders is not an advanced configuration - it is a basic property.
Toggle menu for PSU from LCD pannel

From the prepare menu, accessible when is not printing, you have the
possibility to turn off the PSU when is on et vice versa.
From the host, you can turn off or turn on the PSU then the menu is
updated accordingly.
From the LCD message, the printer status is reported ready or off
respectively when the PSU is on or off.
Turn off power supply off-load

Disable the high current output and wait a little before to turn off,
because the interrupting capacity of the PSU is unknown.
Could be a function if needed by other.
No bed config for RAMPS

The motherboard 35 is a config without bed with this pins setting :
D8 Extruder
D9 Fan
D10 Controller Fan
Merge remote-tracking branch 'upstream/Marlin_v1' into Marlin_v1
Rework change to incorporate CONTROLLERFAN

Also refactor extruder auto fan logic to simplify further and now only
check every 2.5 seconds
Remove unnecessary pin initialization in stepper.cpp

(duplicates initialization in Marlin_main.cpp)