Fixup controller status messages (3 of them)
Merge branch 'sjc-controller-status-msgs' into cd4-controller-status

Conflicts:
	ofproto/connmgr.c
Make async indeterminate length, since it contains TLVs
Merge branch 'sjc-controller-status-msgs' of http://github.com/johndrew/openvswitch into cd4-controller-status
Working on testing a controller_status_async msg is sent when a role is changed (gulf-11946). There are some issues so I am committing so others can look at it.