Override Feed Rates

Added two options:

1. -G0 FeedRate
2. -G1 FeedRate

These options override the file feed rates (i.e. deletes feed rates in the file and uses the option rate instead).

Example:

GCodeFilter.exe -i fish6.nc -o LaserFish6.nc -t 0.01 -l -g0 600 -g1 120

This line (usually in a batch file) overrides both the G0 and the G1 feed rates. Also sets "laser" mode.

AlanX