Django -> 1.7c2

In preparation for setting up a table for user data for the configurable
dashboard, I thought it would be a good opportunity to try Django 1.7's
built-in migrations.

I've followed the instructions here:
https://docs.djangoproject.com/en/dev/topics/migrations/#upgrading-from-south
- Deleted south migrations
- Ran ./manage.py makemigrations

There were also some changes necessary to the casper integration tests.
They seemed to be in bad shape -- maybe they weren't getting run
correctly? I've corrected the window size, and fixed some tests here.
need to switch the claim app over to new migrations as well
Merge branch 'nikolas-django-1.7'