Add License to OVSDB Repo

OVSDB doesn't have the full text of the EPL in the base of the repo.
Other projects (controller, vtn etc...) do. This commit adds the
license.

Change-Id: I0adb2f0d8726fda718d285e596dd2ab3f51329fc
Signed-off-by: Dave Tucker <djt@redhat.com>
Merge "Add License to OVSDB Repo"