Added 'cura ultimaker2 serial/usb driver'.
Ignore vim swap files.
Added a new checkbox to set 'store only' operation of the um2usb driver.
Ignore more temporary vim files.
Added ultiprint.py for Preprocessor class (gcode compression).
Added mor UM2 USB print interface methods.
Added Um2UsbConnection to the list of possible printers.
Some changes to allow codereuse from the Um2UsbConnection* classes.
Reordered sections.