07-March-2015 - 10 hours : Cleaned up the exporters code a lot. Added ppm and feedrate detection from
the layer name. Updated the gcode that is exported to be neater and work better with
pulsed mode using G01, G02 and G03 commands.

07-March-2015 - Fixed the G28 command at the end of the job. Added defaults for laser power,
feedrates and ppm if defined. If ppm isn't defined in the layer options it will operate as
continuous wave mode. See the help in the extension dialog for how to use.

07-March-2015 - Marlin codebase mod : You need to patch the Marlin codebase to turn on the
laser before moving for G02 and G03 commands. This plugin assumes this has been done. More
details to come in the future. Copy the code from the G01 above in marlin_main.cpp