Synchronize code from oslo

Use commit eaab5fae2502198e9fa57d0d90a7204a2bd83b16:
Merge "sort options to make --help output prettier"
(Wed Feb 13 12:52:14 2013 +0000)

Add processutils to quantum since impl_zmq depends on them.

Drop notifier.list_notifier that is not present in oslo.

Change-Id: I91d9ec05481b8c24da9fbee1ad4706ff56a3b7aa
Fixes: bug #1116290
Merge "Synchronize code from oslo"