Check how Decimals should be encoded in tables.  The docs
are a bit unclear, and looking at RabbitMQ and py-qpid
didn't help much.  At least it should work when the
sender and receiver are both using this version of this library.

Error handling, a bit rough in this first version, receiving
unexpected frames may do strange things.

Nothing is done at all with heartbeat, oob-method, oob-header
oob-body, and trace frames.

Unittests - always can use more