Project listing behat feature, new login template and login feature behat updates

This PR adds a feature for the Project browser / filtering behaviours and also fixes some issues with the test environment configuration to ease running the behavioural tests.

Now also merged in the new login template, which updates the login behat feature to work with the new content.

TODO:

- [x] Fix application route issue (XHR requests need `/app_test.php/` prefixing to their route in test environment)
- [x] Fix session storage issue in test environment (keeps falling back to mock session storage)
- [x] Fix issue preventing `App.Router` from triggering routing
- [x] Add scenario for testing pagination of projects
- [x] Fix issue with paging not maintaining filters
- [x] Add scenario for refresh button functionality
- [x] Add scenario for testing empty projects listing