All requested features have now been implemented and tested. This
includes left and right filament scaling, tmperature overrides and
ditto printing. Slic3r post processing is also supported natively.
All suppoted G and M codes are now implemented, and the output from the
lint.gcode unit test has been compared to that of ReplicatorG to
confirm equivilance.
Changed references to tool to extruder - reads better. Added string
clipping to M70 command to prevent buffer overruns. Added machined
definiions for replicator single and dual. Fixed HBP extruder_id
behaviour.