Provide some features to work with rabbitmq.

Influenced by https://github.com/williamsjj/txamqp-helpers and own private library.

Release notes:

0.2.1 and 0.2.2

• Various fixes

0.2.0

• Add support for msgpack
• Various fixes for content-type support

0.1.9

• Support for content-type based encoding
• Add new options for handling encoding: skip_encoding and skip_decoding
• Remove TimeoutDeferredQueue usage
• Fix delivery_mode. Change default delivery_mode to 1

0.1.8

• Remove hard cjson dependency

0.1.6 and 0.1.7

• Fixes

0.1.5

• Extend tid support handling

0.1.3

• Add NO_REPLY support for SynChan
• Add support for bindings declarations