Update README for standalone install
Update README for standalone install

Add more detail steps so it's more clear for new users.

Change-Id: Id521da035e8ad9ad9ccfa569af941769f99f62b4

ekcs/congress,ramineni/my_congress,ramineni/my_congress,ramineni/my_congress,ekcs/congress,openstack/congress,ramineni/my_congress,openstack/congress,ekcs/congress,ekcs/congress