Bug 1103383 - Use remote store for integration tracking +autoland

This is needed to be able to properly deploy and keep current integrations going. It is also needed in order to properly rebuild the integration branch after a deploy or restart.

https://bugzilla.mozilla.org/show_bug.cgi?id=1103383

Tests passing with change:
![screen shot 2014-11-24 at 6 26 51 am](https://cloud.githubusercontent.com/assets/122602/5166201/e9486e54-73a2-11e4-9929-5fb38073d240.png)

This should be configurable and your local tests ideally should not use the same one as prod