The purpose of this patch set is to provide the end users with
the following functionalities:
1. Create volume metadata for a given volume.
2. Get the list of metadata for a given volume.
3. Update a given volume's metadata.
4. Delete an existing metadata of a given volume.
Change-Id: Id10eb6b9b68fcb2c496d1e8fa4fecec3c8d613d8