Backport of Qpid transport from master to 3.0 release stream

This code is compliant with 2.6, and was originally designed to run against the 3.0 release stream. It is the same as master, except for two things:

* OrderedDict is provided from kombu.utils.compat in the 3.0 release stream. This has been adjusted to use that.

* The doc backporting involved some adjustments because of documentation differences between master and the 3.0 release stream.