Remove girl_friday.

It's not currently in use, and we'll be moving to sucker_punch soon
anyway.
Move to Analysand 3.0.0.
Target latest Rubinius.
Relock gem environment.
Ember.js 1.0.0.rc6.

Also drag in Ember Data 0.13.
Don't explicitly create the application's store.

Ember Data will handle this for us.