Subpackage for utilities

[Johannes Schönberger]

Hi,

I would suggest to create a directory like `util/shared` and put all necessary `.py`, `.pxd` and `.pyx` files in there. As Tony said I would put all functions in there that are used from different packages and that might in future be of use for other code. (like integral images, pnpoly, bilinear interpolation etc.)

Johannes Schönberger