Merge pull request #411 from wolfmanjm/upstreamedge

fix panel value setting
Fix bed temp setting when multi extruder is configured
Refactor AutoPid, now handles M302 itself
Make tool manager ignore tools requests it does not manage
fix auto pid refactor bug
need to enable the extruder if it is the only one
Merge pull request #412 from wolfmanjm/fix/multi-extruder-bed

Fix/multi extruder bed
added pause and resume commands to SimpleShell
this system enables a solution for active endstops demonstrated in the Smoothieboard ConfigSample
moved Pauser into Robot (implemented Modules should not be in libs)
renamed pause and resume commands to freeze and unfreeze
Update config
Update config
update firmware.bin
moved freeze and unfreeze commands into PauseButton
Merge pull request #413 from logxen/pausecmd

added freeze and unfreeze commands to PauseButton
added filament_diameter config setting to Extruder to make volumetric extrusion easier to enable
if filament_diameter is not set or is 0 (or less) then the steps_per_millimeter will be left unaltered
removed unnecessary members from Extruder
added M200 command to set volumetric/linear extrusion mode
Merge pull request #414 from logxen/volumetric

Volumetric extrusion
extended volumetric settings into M92 and M500/M503
Add filament diameter to panel settings
M503 should return steps/mm setting
set the minimum filament diameter to 0.01mm to prevent potential rounding issues
save some ram by not making public data returns static data
Combine some bools to bits