"make stop" leaves maas-provision start-cluster-controller hanging around, preventing "make start" from working

[Robie Basak]

Present in trunk revision 1344.

If I run "make start" and then "make stop", I end up in a situation where a subsequent attempt to "make start" hangs with the following message:
setlock: fatal: unable to lock /run/lock/maas.dev.cluster-worker: temporary failure

This appears to be due to a process not stopped by "make stop":

    11800 pts/0 S 0:00 /home/ubuntu/maas/bin/python2.7 /home/ubuntu/maas/bin/maas-provision start-cluster-controller http://0.0.0.0:5240/ -u ubuntu -g ubuntu

(this is in addition to the need to "pkill -9 celeryd" which is a separate bug)

Workaround: sending this process a TERM after "make stop" seems to work.

I will attach:

before-start: "ps axf" before I did anything
after-start: "ps axf" after running "make start"
after-stop: "ps axf" after running "make stop"