Sync rpc changes from oslo stable/folsom

Contains code from the following oslo commits:

9f938720 Update common code to support pep 1.3.
7e36792c kombu's fanout_cast_to_server was calling wrong method
 - Fixes bug 1074113
c3ec615c LOG.exception() should only be used in exception handler
17c5188c Use pep8 v1.3.3
d147d9f2 Fix QPID reconnect issues
 - Fixes bug 1073999

Change-Id: Ia4504cb4d8f2108b743efc4639450254d6e3fb8e
Merge "Sync rpc changes from oslo stable/folsom" into stable/folsom