Incorporate libraries needed by Pillow

[Belgand]

Pillow is being used to validate the images users update for their avatar. The problem is that it needs libraries to read the various file formats people might throw at it or it won't validate them and Django will say they aren't images and won't add them. We should probably be supporting PNG and JPEG at a minimum, and likely GIF as well.

[Belgand]

It doesn't appear that there's any way to install the needed libraries through buildout. I'm going to close this under the premise that it's something we can't actually do.