Add consul support to netplugin/netmaster

[erikh]

https://github.com/contiv/ansible/tree/master/roles/contiv_network/templates is probably where you need to start looking.

Be sure to employ defaults. they live in roles/contiv_network/defaults. Use them and set them to sane defaults. They are very important to the overall UX of our ansible.

What likely needs to happen is that you need a way to generate the URL of the consul and etcd endpoints, so then you can pass either as an argument. The default should be etcd and using consul should mean supplying another url.

Summary:

• adjust templates to accept a cluster_url argument and turn on the right cluster_store.
• set a default for each of the above variables in the contiv_network/defaults/main.yml file.
• maybe create an example of global vars in group_vars/examples if you have time.