Protocol 0.2.0

Update to the protocol as a result of libchan meeting with Matteo Collina.
Bump the version to 0.2.0 and name the set the previous version as 0.1.0.

Protocol changes:
 - Define stream provider to support multiple multiplexing protocols
 - Support CBOR in addition to Msgpack for channel message encoding
 - Add extended type codes definition
 - Require byte-streams to send *"libchan-parent-ref"*
 - Allow byte-streams as duplex or half-duplex
 - Add channel synchronization through ack definition
 - Add channel errors
 - Update description of relationship to Go channels
 - Add stream content type

Other changes:
 - Add Derek and Matteo to authors
 - Reformatted to 80 character lines
 - Much cleanup and rewording

Signed-off-by: Derek McGowan <[email protected]> (github: dmcgowan)