Updates python-kombu to 3.0.24

This updates python-kombu to 3.0.24 which is vanilla from upstream! This is behaviorally identical with the downstream patched version we were carrying just prior to this update python-kombu-3.0.1-13. The release we were carrying had 2 patches in it, but I verified those are both contained in 3.0.24 without any spec file patches.

With the switch to 3.0.24, python-amqp now requires version 1.4.6 instead of 1.4.5. That dependency is also already built in koji so this is ready to build!

I've done test scratch builds on FC19, FC20, EL6, and EL7 already. You can see they all passed.

http://koji.katello.org/koji/taskinfo?taskID=198066
http://koji.katello.org/koji/taskinfo?taskID=198065
http://koji.katello.org/koji/taskinfo?taskID=198064
http://koji.katello.org/koji/taskinfo?taskID=198063