Finished the SQLite Repository implementation

It was incredibly difficult to get SQLite up and running in a way that
was elegant, and well-tested. I could not get it with my MsTests. I
could not get it working with the NUnit tests on the iPhone simulator
because monotouch and Xamarin.iOS are not compatible. Ultimately, I will
have to create temporary tests on an undeployed app, which is far from
idea.