Another attempt at #81

[tgriesser]

This'll make doing #101 and other data model related items much easier.

[tgriesser]

Also, it creates a separate ghost namespace'd database instance, so it doesn't conflict if other people happen to be using Bookshelf/Knex alongside their app.

It also moves filterCallbacks and filters off the prototype, because you almost never want to specify arrays or objects directly on the prototype unless you're sure you're never going to modify them from new instances (which we aren't in this case because it's a singleton, but that's beside the point)...

Because javascript is pass-by-reference for object values, you generally don't want objects/arrays on the prototype, always in the constructor.