v1.3.1

Changes from 1.3.0:

• Implemented Step & Repeat
• Full support for image polarity
• Implemented region cut-ins
• Implemented outline-width
• Fixed RS274X macros
• Optimised multi-step engraving
• Fixed toolpath masking (#37)
• Added contentions warning
• Renamed --g64 to --tolerance
• Added --nog64 (#35)

Not working:

• Output debug image (buggy)