Fixed the plane vector equation to a simpler one (only dependent on the normal)

Removed the calculation of the inverse matrix since the rotation matrix is orthogonal, therefore inverted == transposed.
Much simpler and mathematically robust.
Implemented a least squares fit of the bed equation for auto bed leveling.

The code for the LSQ solver (qr_solve) is copyrighted by John Burkardt and released under LGPL here:
http://people.sc.fsu.edu/~%20jburkardt/c_src/qr_solve/qr_solve.html
(see qr_solve.cpp for further copyright information)
Made numbering of heat bed thermistor more logical as D8 is bed, D9 is Extruder 2 and D10 is Extruder 1, so T0 should be E1, T1 E1 and T2 bed to be sequential as MOSFET-Outputs
Added posibility to set ENCODER_STEPS_PER_MENU_ITEM in Configuration.h like ENCODER_PULSES_PER_STEP as it depends on it for usability
Incorporate PS_DEFAULT_OFF for starting state on LCD menu entry
Minor code and comment polishing
Accurate bed leveling: x loop inside y and zigzag motion
Revert "Made numbering of heat bed thermistor more logical as D8 is bed, D9 is Extruder 2 and D10 is Extruder 1, so T0 should be E1, T1 E1 and T2 bed to be sequential as MOSFET-Outputs"

This reverts commit b7eadb9f37971a9a2cb0b55a3cca0d013d4e6351.
Merge pull request #676 from IVI053/Marlin_v1

Minor improvements for encoder configuration, LCD entry for PSU controll and thermistor pins on RAMPS
Update Delta example files

Signed-off-by: Joseivaldo Benito Junior <jrbenito@benito.qsl.br>
Merge pull request #684 from jrbenito/update_delta_config_examples

Update Delta example files
Correct missing parameter from last upmerge

Signed-off-by: Joseivaldo Benito Junior <jrbenito@benito.qsl.br>
Merge pull request #687 from jrbenito/update_delta_config_examples

Correct missing parameter from last upmerge
Merge branch 'Marlin_v1' of https://github.com/ErikZalm/Marlin into ErikZalm

Conflicts:
	Marlin/Configuration.h
	Marlin/Marlin_main.cpp
Merge pull request #673 from fsantini/ErikZalm

Improvements to the auto bed leveling feature
Add Ultiboard2 electronics. With PWM current settings. For the few people that have this new board as experiment in their UM-Original.
Added PT100 support for Ultiboard2
Merge branch 'Marlin_v1' of https://github.com/ErikZalm/Marlin into Marlin_v1