Fix for Issue #17: allEntries on schemas with new lines (JSON-ified)

Integrated google-gson for more reliable serialization over the wire.
Added tests for JSON.
Client tests now submitted to persistence/multi-line tests.
See, for ex., this for the way to access a header (it would be `Accept` in our case)
http://www.mkyong.com/webservices/jax-rs/get-http-header-in-jax-rs/