Update this repo with releases to support both OCP v3 and v4

[oybed]

With some of the latest changes, this repo may no longer be OCP v3 compatible, and we need to come up with a good strategy to be able to support both v3.x and v4.x. The current releases are named v3.* and this is confusing, especially as these aren't OCP v3.x compatible. In hindsight, it would have been better to not use v3 as part of the release naming, but at this point we need to solve this in a way to avoid this conflict. Perhaps we start 2 release threads, i.e.: one for v3.x and another for v4.x, but this may generate extra overhead work for maintaining it.

Let's discuss.

[briantward]

Yeah, I second this, ran into it myself.

[briantward]

How about a release-3.x and release-4.x branch? I've already got changes for some tags for 4, along with a suggestion to switch to registry.redhat.io/openshift4/ose-cli for the base oc commands