adding some docs for L3 and HA
adding some docs for L3 and HA

Signed-off-by: Dan Radez <73b4a7191a9f1d7e703563c882d9d4b245d19df3@redhat.com>

umeshksingla/puppet-opendaylight,umeshksingla/puppet-opendaylight,srisankethu/puppet-opendaylight,trozet/puppet-opendaylight,srisankethu/puppet-opendaylight,trozet/puppet-opendaylight