Add Documentation for OVSDB

Add Documentation for OVSDB

lfdocs-conf is a new project that allows us to centrally manage
project theme configuration without having to duplicate it
everywhere or have the "docs" project become a large submodule
project.

We will push to ReadTheDocs separately and then create a new path
for this doc under docs.opendaylight.org/projects/integration-packaging

For further details refer to:
http://docs.releng.linuxfoundation.org/en/latest/project-documentation.html

JIRA: DOCS-69
Change-Id: Ibd03538877a5078aae5c6b87dce8be5a6c0dae7e
Signed-off-by: Nobin Mathew <nobin.mathew@ericsson.com>
Signed-off-by: Anil Belur <abelur@linuxfoundation.org>