Add bridge_mappings to extras/80-opendaylight.sh to support vlan isolation.

OpenDaylight integration with Openstack requires some extra configuration
information to be set in the ovsdb via the other_config value. Currently
only the local ip address is set. bridge_mappings needs to be added to support
vlan isolation.

This requires changing the form of the existing ovs-vsctl command to set
the other_config value. The current command does a replace so the last
command to run overwrites any other values. The command is changed to
append values instead.

Change-Id: Ia001ecf27c8f5ace05af014ecce0b13f6d490ac1
Merge "Add bridge_mappings to extras/80-opendaylight.sh to support vlan isolation."