Update the OpenDaylight support to the Helium release

The OpenDaylight project recently released their latest release, codenamed
Helium. This commit updates the devstack support for OpenDaylight to this
new version, which includes changes to configuration files as well as the
startup of OpenDaylight itself.

Also update my email address in MAINTAINERS.rst.

Change-Id: I124b5e7e8ef7feb6c90de907916a9530409c4ad4
ofagent: Support physical_interface_mappings

Also, add a knob to create a veth pair instead of a bridge
to provide host connectivity for l3-agent.  (Q_USE_PUBLIC_VETH)

Related: blueprint ofagent-physical-interface-mappings
Change-Id: I4c2538f0fd3fb05bfdb69e7e4c3a8462af42ba10
Merge "Update the OpenDaylight support to the Helium release"
Merge "ofagent: Support physical_interface_mappings"