Update README with instructions on how to update bundles in karaf
Update README with instructions on how to update bundles in karaf

Change-Id: Ied0613a4ec961f668c5b5587cd65b3f13edfcfef
Signed-off-by: Sam Hague <0bd82f91a319b8977788d8264eb020ecd4ace960@redhat.com>

opendaylight/netvirt,opendaylight/netvirt,opendaylight/netvirt,opendaylight/netvirt,opendaylight/netvirt