Use Zeitgeist for History

Zeitgeist's sole reason for existence is to bring the element of human contextual awareness to computer systems, paving the way for more user friendly and easier to use software. That's something we want.

Zeitgeist is designed to efficiently store metadata about user activity. Having another history implementation is both redundant and unnecessary when we can (and should!) just plug into Zeitgeist.

In addition to making browser history available to other apps, Zeitgeist also gives us better intelligent sorting/searching than we could implement on our own. We also get to pull in other relevant data as we see fit.