Disable custom init script for rabbitmq on Fuel Master

Custom init script breaks deployment when
hostname changes, but it is not necessary
to have HA enhancements in init script for
Docker non-HA deployments.

Additionally, explicitly create / vhost for
nailgun and astute.

Change-Id: I1524bc3bfccf74e05418189ad15642f25b14acce
Closes-Bug: #1337322