README: update links and more
README: update links and more

This is in response to #65.

We still need to render rdopkg manual online.

Change-Id: I743a4c13fe767c3673bb559ad5293bcf51c95ca3

openstack-packages/rdopkg,openstack-packages/rdopkg,redhat-openstack/rdopkg,redhat-openstack/rdopkg