Creating a cluster from scratch takes about 7 minutes. But if you just
rebuild the binaries and want to update those you don't want to have to
rerun the entire thing. There is an ansible tag 'binary-update' which
will do that. Now one can do
```
ANSIBLE_TAGS=binary-update vagrant provision
```
And it will push the new binaries.
Do the /etc/host creation with vagrant, so it uses internal instead of
external ips (hostmanager only knew about the public ip)
Ignore errors on docker failure when 'restarting' docker in flannel
handler. If this is a clean install, we haven't run 'node' yet so docker
isn't installed so it doesn't need to be started. It would be better to
be more specific in ignoring errors though...
Eric Paris