Prototype implementation of oslo.versionedobjects.
This patch adds WatchRule and WatchData object.
Implements: blueprint versioned-objects
Co-Authored-By: ShaoHe Feng <shaohe.feng@intel.com>
Co-Authored-By: He Jie Xu <hejie.xu@intel.com>
Co-Authored-By: Grzegorz Grasza <grzegorz.grasza@intel.com>
Change-Id: I29fc0fc99c0c425291246dc3889393cbcc0b82cf