Starting PWM timer code.
Merge branch 'alden' into rob
PWM on SAM works!
Rearranged how pin assignments are done.

Now separating boards from projects.

Updated XCode project.

Have **not** updated the AS project yet.
Merge remote-tracking branch 'refs/remotes/main/alden' into rob

Conflicts:
	TinyG2/controller.cpp
	TinyG2/controller.h
Finishing up the pin cleanup.
Cleanup of vrefs. Set default of 50% vref.