Speed ups

[Juan Pablo Caram]

1) G-code parsing is probably very slow and can be sped up using regular expressions. Not true: Generating the geometry and plotting takes most of the time. 2) Store the geometry generated when plotting and use that for further plot requests unless something has changed since. 3) Simplify the geometry before plotting. Skip points if they are too close together. Perhaps use Shapely's simplify feature.

[Juan Pablo Caram]

G-Code manipulation was very slow because individual Shapely objects where being created for each segment. Now it is fast enough and no other tasks seem to be slow.

[Juan Pablo Caram]

Support for more Gerber features has driven the parser to become really slow.

[Juan Pablo Caram]

Storing polygons in a list only until there is a need to join them improves speed by ~100.