Use TLS proxy for neutron server's internal TLS

Use TLS proxy for neutron server's internal TLS

This uses the tls_proxy resource added in a previous commit [1] in
front of the neutron server when internal TLS is enabled. Right
now values are passed quite manually, but a subsequent commit will use
t-h-t to pass the appropriate hieradata, and then we'll be able to
clean it up from here.

Note that the proxy is only deployed when internal TLS is enabled.

[1] I82243fd3acfe4f23aab373116b78e1daf9d08467

bp tls-via-certmonger

Change-Id: I6dfbf49f45aef9f47e58b5c0dbedd2b4e239979e