Backed out OVSDB support code temporarily.

OVSDB support that uses new APIs will be enabled later.

Other changes:

  * integrationtest: Ensure that the VTN neutron bundle can be loaded.
  * northboundIT: Ditto.

Change-Id: Ic7ccffc292d6569b59fda144b8c7bb3753fcc6ff
Signed-off-by: Shigeru Yasuda <s-yasuda@da.jp.nec.com>
Merge "Backed out OVSDB support code temporarily."