392.20	Adding new model getters and setters
intermediate commit
392.21 Replaced a bunch more MODEL layer setters and getters
392.22 Starting work on more complex getters and setters like offsets
392.23 cm_get_work_offsets()
392.24 cm_set_move_times()
392.25 substituting cm_get_coord_offset(axis)
392.26 reverted to cm_get_model_coord_offset()
392.27 cm_get_work_offset()
392.28 Switched in cm_get_work_position()
392.29 cm_get_machine_position()
392.30 Commented out some unused prototypes