We currently pass a lot of options all the way from RBClient to the

transport to ReviewBoardServer, and this list has continued to grow

over time. We will soon be needing another option, and instead of

continuing to add dedicated options, we're now passing the loaded

configuration instead.
RBToolsConfig was added in RBTools 5, and consolidates all of our

loaded options. This is easier to populate/load and pass around.

RBClient, SyncTransport, and ReviewBoardServer now all take this

as arguments.
If this is not provided, ReviewBoardServer will load a configuration.

This avoids breaking API compatibility with any custom scripts or hooks.

The loaded configuration will always be explicitly provided when being

run from a command.

Unit tests passed.
Successfully posted this change for review.
Made use of the configuration in an in-progress change.