Include alembic versions directory to the package
Include alembic versions directory to the package

If package is built without access to git metadata, all the migration
scripts are not included in the build. We need to explicitly specify to
package the scripts.

This patch also removes non-existing files from MANIFEST.in

Change-Id: I840d2bd8b61268891007f9ae1082d89e33d90373
Closes-Bug: #1658899

zeinsteinz/tacker,openstack/tacker,stackforge/tacker,stackforge/tacker,openstack/tacker,zeinsteinz/tacker,openstack/tacker