half-way commit to explain some of what is going on
working code, only one bug left
mostly working, needs extruder support
Merge branch 'edge' into stepper

Conflicts:
	gcc4mbed/build/mbed.ld
	src/main.cpp
small optimisation
adding the Endstop module, first commit
basic homing
wheee, basic homing
more endstops progress, needs final move
testing on smoothieboard, with steppers, trying to make it work correctly
yay, big stepper branch bug solved, we forgot to set speed to initial_rate because we stopped setting speed at block change
stepper code now only iterates on stepper motors that are actually active, thus saving precious time, yay !
corrected some problems with the enable pins gcodes
merging edge into stepper, correcting conflicts
merging edge into stepper
reworking the extruder module to work with the new stepper subsystem
commiting just to show the new configvalue class
solved the block end problem, commiting mostly to save all those neat debug statements in case they are needed again
saving the new acceleration system before reverting it
the fast move end bug is fixed, re-working the stepper system once again