Copy Cat Cracker Cutter

Cat tessellation based on a design by [Makoto Nakamura](http://tessellation.info/en/info/artists/5/d/199/Cats). Polygon point locations were guessed from a surface plot of a thresholded greyscale version of the image.

The press has been updated following an idea to use the path extrusion as per [mbrembati's cookie cutter](http://www.thingiverse.com/thing:1607586).

Path extrusion didn't work so well for the cylindrical repeating version due to incorrect rotations, so I fell back to a more basic hull() operation.