UC-18 Add Tracking for Facebook interactions

Do not merge yet

We need a way to independently track user Facebook interactions (login, connect, disconnect, logout...)
This PR adds those tracking code, so that we can track these actions internally and on GA.

RFCR @garthwebb & @lizlux 

Ticket: https://wikia-inc.atlassian.net/browse/UC-18
Fun thing about this file: it's not wrapped in a closure. So every function and variable that are defined here are global. You just added two new global variables! ;)

One way to fix this would be to wrap the entire document in a closure and make sure you expose the current globals to the ```window``` namespace. Or you can make these vars local to the functions they are used in (less awesome but affects less code). Not sure if we're treating this as a 3rd party script or if we're taking it on as our own.