[watcher] Transition Ussuri to EM

This transition the ussuri branch to extended maintenance.
Changes for bugfixes and things the team deems important are
still encouraged, but there will no longer be official releases
off of the branch.

Please +1 if the team is ready for us to proceed with this
transition, or -1 if there are any final backports currently in
flight that we should wait for. For the latter case, please
update the patch with the new commit hash after doing a final
release to get those changes out so we know to proceed with the
transition.

Change-Id: I45b47aa98974b0db8d29e88ba49c2b99a34ede5a

deliverables/ussuri/python-watcherclient.yaml

@@ -15,6 +15,10 @@ releases:
     projects:
       - repo: openstack/python-watcherclient
         hash: 5946fbb5b1f316a9b0e2509e06a318993930e8e4
+  - version: ussuri-em
+    projects:
+      - repo: openstack/python-watcherclient
+        hash: 5946fbb5b1f316a9b0e2509e06a318993930e8e4
 branches:
   - name: stable/ussuri
     location: 3.0.0

deliverables/ussuri/watcher-dashboard.yaml

@@ -20,6 +20,10 @@ releases:
     projects:
       - repo: openstack/watcher-dashboard
         hash: abcd7c04b27409b08b62c4311944bbe3a24b1ccd
+  - version: ussuri-em
+    projects:
+      - repo: openstack/watcher-dashboard
+        hash: abcd7c04b27409b08b62c4311944bbe3a24b1ccd
 branches:
   - name: stable/ussuri
     location: 3.0.0.0rc1

deliverables/ussuri/watcher.yaml

@@ -33,6 +33,10 @@ releases:
     projects:
       - repo: openstack/watcher
         hash: 2e033d7b96eb4cb47642909cda5a87a4ec4e0fe9
+  - version: ussuri-em
+    projects:
+      - repo: openstack/watcher
+        hash: 2e033d7b96eb4cb47642909cda5a87a4ec4e0fe9
 branches:
   - name: stable/ussuri
     location: 4.0.0.0rc1