Added rjil::zookeeper

Added contrail dependency zookeeper. This need hiera entry
'zookeeper::id' which must be unique for each zookeeper servers
in the cluster. So in case of multi-node contrail setup, the hiera config
need to be overridden in clientcert level for those nodes.
can we just auto-generate these by default? Given that we won't know the names of the hosts ahead of time, I don't understand how this is supposed to work. What if we just default this to $::hostname ?