This patch integrates Port Binding Level OVO in /plugin/ml2/db.py
and introduces context instead of session for usage in object
operations.
Change-Id: Ifa779f5f70a7502bd96b34d64a84d272af2a6886
Partially-Implements: blueprint adopt-oslo-versioned-objects-for-db
Co-Authored-By: Anindita Das <anindita.das@intel.com>
Co-Authored-By: Slawek Kaplonski <slawek@kaplonski.pl>