#31 Move to Jackson for all JSON processing

[Derek Battams]

Initial versions of the API use the org.json library for JSON processing, which is fine for PoC kind of stuff, but it definitely needs to be replaced with something more robust/faster, like the Jackson library.

Nothing from the org.json library is exposed in the public API so it's just a matter of stripping it out and replacing it, which won't be hard, but will be a bit tedious. Should result in some significant performance gains though... when I actually get around to doing it.