Change User Log In from Alert

[quadrophobiac]

#252 indicates a need for a user interface for deleting endpoints for an authenticated user.
#257 needs to be able to test for an authenticated user - currently user logs in via an alert and Capybara has limited ability to interact with alerts (accept or dismiss, rather than fill_in being available)
Currently a user may log in but may not log out - this is expected functionality that should be implemented