Safe version checking

[jmontleon]

There are at least a couple places we need to know the version of the openshift cluster in order to do things "the right way" (such as create an SCC and use a rolebinding and role to give a user a privilege, vs. a role/rolebinding that grants the use verb on an existing SCC).

The checks right now are basic, mostly looking at the kubernetes minor version, similar to what we've done in migration-controller, but perhaps there is a better way.

Also, some history, back around the QCI days we were using an OpenShift version API, but that was removed around somewhere around 3.10 and we could no longer rely on it, which is how we got here with crane-lib/mig-controller.