Fix migrations and their dependencies.

Setting up a site from scratch (or running tests) wasn't working because:
- manage.py was moved up one directory, so some places where we used a
  relative path needed to be updated
- tagdict was switched over to migrations, but it turned out that the
  ESPUser code was doing a query with Tags, so we needed a dependency
  there
Remove reference to pspicture Latex library

I recommend that any Latex libraries needed be installed on the server as
a prerequisite; it doesn't make sense for our repository to provide them
(and copy them into the working directory?) if they aren't developed by
us.
Fix some Javascript syntax errors that would show up in IE

I didn't even do any testing yet; these were pointed out by our automated
Closure compiler test.