Add SCARAcal to Smoothieware
Required for easy SCARA calibration, using M360 M361 and M364 calibration routines as
described in http://reprap.org/wiki/G-code

 Changes to be committed:
	modified:   src/main.cpp
	new file:   src/modules/tools/scaracal/SCARAcal.cpp
	new file:   src/modules/tools/scaracal/SCARAcal.h
Merge pull request #452 from wolfmanjm/upstreamedge

fix G90/91 for Extruder
Merge remote-tracking branch 'upstream/edge' into edge
Cleaned up code for pull request
 Changes to be committed:
	modified:   src/modules/tools/scaracal/SCARAcal.cpp
	modified:   src/modules/tools/scaracal/SCARAcal.h
update fimware.bin
Removed unused event handler, and repaired M114 format
Simplified SCARA_ang_move()
snprintf in SCARA_ang_move
Merge pull request #453 from RepRapMorgan/SCARAcal

Add SCARAcal to Smoothieware
add md5 checksum for binary file
Merge branch 'edge' of github.com:Smoothieware/Smoothieware into edge
Add enabling of limit switches which will freeze operations if any limit switch is triggered while printing
fix typo
fix pause button to be able to unpause system regardless of what caused it to pause.
fix wait for temperature so multiple waits don't lock system indefinitely
add some TODO notes
don; tlet pauser counter go negative
fixed use of pause in other modules
Merge pull request #457 from wolfmanjm/add/limit-switch-stop

Add/limit switch stop
show status of all connected endstops with M119