[WIP] Add Openstack SSL Support

Allow Openstack connections to be protected with SSL.

Additionally, remove some unused methods in `EmsOpenstack`.

WIP: Looking at how to add tests for this.
Breaking your questions apart:
1) which fallback is correct?

We have to try non-ssl first to get the correct failure condition in order to know whether to even try ssl.

2)  Does it make sense to even fall back?  Why not just error out if it doesn't respond as configured?

The problem here is that I've found out from various configurations that there are different ways to configure SSL for OpenStack.  The most devious way is to configure SSL for OpenStack services, but use the exact same ports as they would normally use.  This leaves us *no* way to determine based solely on the incoming parameters associated with the Provider whether it's "configured" for SSL or not.  It's simply a connection without context.

So, we have to try non-ssl.  If it works without SSL, then we proceed as normal.  If it blows up with the specific error noted in this method, then we retry the connection with SSL.