Fix build/install errors in routermanager branch

Fix build/install errors in routermanager branch

This patch addresses the following errors in routermanager branch.

Build error: Failed to execute goal org.apache.karaf.tooling:karaf-maven-plugin
             :3.0.3:features-create-kar (features-create-kar) on project
             routemgr-features: Cannot find version for: com.google.code.gson/gson/

Install error: Addressed this issue by merging few patches from master branch.
              $opendaylight-user@root>feature:install odl-ovsdb-openstack
              Error executing command: Can't install feature odl-ovsdb-openstack/0.0.0:
              Could not start bundle mvn:org.opendaylight.ovsdb/openstack.net-virt/1.3.0-SNAPSHOT
              in feature(s) odl-ovsdb-openstack-clusteraware-1.3.0-SNAPSHOT,
              odl-ovsdb-openstack-1.3.0-SNAPSHOT: The bundle "org.opendaylight.ovsdb.openstack.
              net-virt_1.3.0.SNAPSHOT [281]" could not be resolved. Reason: Missing Constraint:
              Import-Package: org.apache.commons.net.util; version="[3.4.0,4.0.0)"

Change-Id: I351398950d6fe3c2043d9bfe71a429cf7b5182aa
Signed-off-by: Sridhar Gaddam <sgaddam@redhat.com>