XD-431 - Make toString() payload conversion optional
XD-431 - Performance optimization to prevent calling resolvePayloadTransformerForMessage() on every message if there is no transformer
XD-444 Add RedisAvailableRule to New Test

Missed in previous commit.
XD-401 Post data to http endpoint
Added command line option "post http" with "--target" and "--data" options
Added support to output request/response/error as handled in rest-shell
Added better error handling
XD-384 - Polished Controllers and Deployers
Split Client interface between Streams and Taps
Implemented Exception propagation to the client