Release glance-store 0.15.0

The 0.14.0 failed the glance gate for docs and was blocking the review
queue. So, we need this quick follow up release to fix the glance gate
and use all the commits and fixes proposed therein from the prior one.

More explanation about the same is given in bug 1606746 and bug 1605648

Change-Id: I4d17375d2a716581633a5eb91bd6c44ff0a64ab8

deliverables/newton/glance-store.yaml

@@ -15,3 +15,10 @@ releases:
         project_domain_id for swiftclient driver.
       - Cinder driver now uses image_size metadata instead of volume
         size rounded up to GiB.
+  - version: 0.15.0
+    projects:
+      - repo: openstack/glance_store
+        hash: 10f50da5fcd9257090ab137f4d257940bb01b44a
+    highlights: >
+      - Fixed a critical bug 1606746 that was blocking further
+        releases and failing gate of glance docs.