Fix up docker-admin and bootstrap to run in docker 0.9.

Bringing up an admin node in production will fail at the
provisioner-server role in docker 0.9 right now.  You can work around
this by running:

service httpd restart

and then retrying the failed provisioner-server noderole.  The admin
node shold finish coming up after that.
Merge pull request #76 from VictorLowther/docker-0.9-support

Fix up docker-admin and bootstrap to run in docker 0.9.