Feature tests

Adds lots of feature tests, edits some of the other tests that I didn't finish early and totally forgot about (that's why some tests are now pending instead of passing), adds a seed file so we can run rake db:seed for testing purposes, makes lots of little changes to various forms (holy indentation issues, Batman!) and moves all of the styling to style.css so that application.css is only calling the tree. 

TODO: Finish the session controller and other tests that I totally forgot about earlier.