Create new and more usable REST client

ModeShape's REST client was originally introduced quite some time ago, and we've added quite a bit more functionality to the REST API. In fact, we have a new version of the REST API that is even more functional and easier to use. We can't really change the REST client in a way that is backward compatible.

Therefore, we need a new REST client that:

• exposes the full functionality of the latest REST API, and is able to grow as new functionality is added to the REST API
• will still work (albeit with downgraded functionality) when talking to a 2.x server
• can expose metadata about the server that it's talking to (e.g., version, capabilities, etc.)
• can fully replace the older REST client and its functionality, but should not implement the older REST client interfaces (e.g., it is not a drop-in replacement)
• should be far easier to use (likely a connection-based, stateful design; also perhaps consider a fluent API)
• can be used by the remote JDBC driver (replacing the existing REST client)
• requires a minimal number of JARs