Devise authentication

This ended up being a much larger effort than I anticipated, mainly because of routing issues (lots of changes to routes.rb, so check those out) and some devise idiosyncrasies.  You'll definitely want to run through everything before pulling, and let me know if there are any issues.  

Some notes - I had to change the default password since devise enforces an 8 character minimum.  (This is configurable, but I left it.)  If you run rake db:seed again it will update the password for the existing admin user with the password Funt1me!

Other than that, I made it possible for people to register for admin accounts.  The account will be created, but will need to be approved by an existing admin (rake db:seed also approves the existing admin account).

Nothing too fancy, but should be able to extend now that devise is in place.