Fix #1: Missing location images on anonymous homepage.

The main issue was to use Pillow for building in
a virtualenv rather than PIL. This branch also
switches out sorl.thumbnail for easy_thumbnails.
sorl added some complexity in setup and debugging
that made it hard to work out what was going on.

Also, images for locations are not saved in tree
for development anymore.
Redesign the homepage for easier development.

This provides a simpler UI, which makes it easier
to build the site. This looks ahead to a simple
event-based site that lists events in an endless
scroller style interface.

Interior pages don't work, and there is no nav
in the header. The goal here is only to get the
start of a simple UI.