Embedded API docs via swagger

Based off of @hgschmie's `swagger-experiment` branch. I banged my head against the wall a lot due to the fact that that `swagger-maven-plugin` executes during the compile phase, and my solution seems a little hacky (outputting the HTML file directly into `target/classes/`), but things seem to work.

The documentation page itself needs some more styling in order to look decent, I'll try to take a stab at that over the weekend.

/cc @wsorenson @gchomatas @HiJon89 @hgschmie @stevenschlansker