Fix for thermocouple sensor type.
Fix CRC hopefully for the last time.
Fix heater is_heating initialization
Made a number of queue command fixes.
Added movement checkpoint. Fixed some movement command handling bugs.
Implemented trigger_level configuration for Input_Switches
Fix primary axis calculation
Generate debug message when entering stopped state.

Fix handling of multiple queue packets. Make endstop checking more
efficient when not enabled.
Fix step generation for movement using multiple axes.
Fix to accel/decel to prevent timer rollover
Merge pull request #1 from minnow-pmc/master

Update from head