This keeps the CRD compatible with kubernetes v1.14 and earlier

This allows compatiblity with kubernetes v1.14 and earlier.

Includes prometheus-operator v0.35.1 which should fix the statefulset
crash loop issue #2950

This prevents mismatch between prometheus-operator binary and related
CRD yaml files.

* Avoid race condition when deploying quickstart example

The namespace and CRD creation must happen before any dependent objects
are created.  So we can put these in a separate directory (manifest/setup)
so they can be created before the other objects.

Some minor updates to the README and added a couple of scripts
for the quickstarts

Update travis script to avoid race condition

Signed-off-by: Paul Gier <pgier@redhat.com>

* simplify the example quickstart script and improve readme

Signed-off-by: Paul Gier <pgier@redhat.com>

* increase minikube memory to 6g for quickstart example