Fixed a couple of infinite loops related to automatic adjustment of zIncrement. Not entirely happy with the result. Unit tests would help in this area. Changed how commands are passed their arguments. It's now a string instead of a list as a string is what all the commands need. Added commands for setting the extruder and heated bed temps. Still need to add some extrusion commands. Changed how data is read from the board. Not sure it is the proper way, but it works for now. Added comments on some other incomplete areas in the code. It's amazing how much can still be added. Successfully used this to level the print head, but not at temperature. Need extrusion commands before I'm ready for that.