Trigger refresh of localStorage

[JGulbronson]

We use localStorage to save things like courses, professors, and friends for faster searching. They get periodically refreshed, based on which it is. (i.e. your friends will change more often than courses). It would be nice to have some way to trigger a refresh (possibly when you login).

The use case for this is when there is some bad data in localStorage. Recently we had issues with the Facebook API, which means only 25 friends per user were stored. This won't be fixed until the refresh period for friends.