Update README for release v3.1.1
Update README for release v3.1.1

rgeyer/rsc,lopaka/rsc,rgeyer/rsc,rightscale/rsc,rgeyer/rsc,manuelfelipe/rsc,manuelfelipe/rsc,lopaka/rsc,lopaka/rsc,rightscale/rsc,manuelfelipe/rsc,lopaka/rsc,manuelfelipe/rsc,rgeyer/rsc,rightscale/rsc,rightscale/rsc,rgeyer/rsc,manuelfelipe/rsc,lopaka/rsc,rightscale/rsc