Regression after change 322200 - Kubernetes doesn't allow underscores in configmaps

After this change: https://review.openstack.org/#/c/322200/5

Kolla-Kubernetes suddenly stopped being able to build.

Example run:

```
kolla-kubernetes run mariadb
2016-06-06 23:42:19.487 13791 INFO root [-] Command : ['kubectl', '--server=http://localhost:8080', 'create', 'configmap', 'mariadb-configmap', '--from-file=/etc/kolla/mariadb/config.json', '--from-file=/etc/kolla/mariadb/galera.cnf', '--from-file=/etc/kolla/mariadb/wsrep_notify.sh', '--from-file=/etc/kolla/mariadb/wsrep-notify.sh']
error: wsrep_notify.sh is not a valid key name for a configMap
2016-06-06 23:42:19.531 13791 INFO root [-] Command : ['kubectl', '--server=http://localhost:8080', 'create', '-f', '/tmp/kolla-2016-06-06_23-42-18_3XdTw7/kubernetes']
```

When I try to duplicate that by hand, I get the same message. We can't create a config map with an underscore in the name.