Add note regarding Django 1.6 security improvement.
Replace render_to_response with render

render is the new way of doing it, and is much less boilerplate-ey...
Fix login redirection not working

Fixes #3.
Now, if you go to /plots/boxfill/ and you're not logged-in, it'll send you to

/login/?redir=%2Fplots%2Fboxfill%2F
(the '/'s are encoded as '%2F' by urllib.urlencode())

where, upon logging in, you will be redirected back to where you were.

/plots/boxfill/