Added basic sign in/sign out functionality

User can now sign in and out using their Facebook account. Unfortunately at the moment signing out of the app also signs them out of Facebook, but that's another problem for another day! I've had to add some fairly extensive styles for the login and logout buttons, and I've also found out how to force my view to prod my controller to get the loginStatus model updated. There's some old code, and some Facebook sample code in there, yet to be cleaned up and refactored (it's all commented out), but I'll get to that once I've grabbed the user's basic information and friend list.
Improved debug JSON output and cleaned up code

Added a function to print some half decent JSON output to a page width div and separated out JS Facebook code into its own file.
Modified CSS to prevent login button displaying on page load

Unfortunately for whatever reason this isn't working at the moment but, according to my understanding, the login buttons should no longer display until such time as Angular has monkeyed with their CSS display property (it's now set to none by default). I think I'll need to ask for some help to get to the bottom of this on Monday.