[nova] Transition Train to EM

This transition the train 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: Ic0bca9ee68ccae7d0d17548d2472eb49c3c76968

deliverables/train/nova.yaml

@@ -103,6 +103,10 @@ releases:
     projects:
       - repo: openstack/nova
         hash: 10df17638a1587f740c46a574c923df9348c3344
+  - version: train-em
+    projects:
+      - repo: openstack/nova
+        hash: 10df17638a1587f740c46a574c923df9348c3344
 branches:
   - name: stable/train
     location: 20.0.0.0rc1

deliverables/train/os-vif.yaml

@@ -18,6 +18,10 @@ releases:
       - repo: openstack/os-vif
         hash: 3a08cc4528c183ecf03d1795ca500bb9b745f12d
         tarball-base: os_vif
+  - version: train-em
+    projects:
+      - repo: openstack/os-vif
+        hash: 3a08cc4528c183ecf03d1795ca500bb9b745f12d
 branches:
   - name: stable/train
     location: 1.17.0

deliverables/train/osc-placement.yaml

@@ -15,6 +15,10 @@ releases:
     projects:
       - repo: openstack/osc-placement
         hash: 8bbca01dbddb1eb374d708553ccaddb4f130116e
+  - version: train-em
+    projects:
+      - repo: openstack/osc-placement
+        hash: 8bbca01dbddb1eb374d708553ccaddb4f130116e
 branches:
   - name: stable/train
     location: 1.7.0

deliverables/train/placement.yaml

@@ -43,6 +43,10 @@ releases:
     projects:
       - repo: openstack/placement
         hash: ff55034f10ab0b45ebcc455434fa491efcd3eb7b
+  - version: train-em
+    projects:
+      - repo: openstack/placement
+        hash: ff55034f10ab0b45ebcc455434fa491efcd3eb7b
 branches:
   - name: stable/train
     location: 2.0.0.0rc1

deliverables/train/python-novaclient.yaml

@@ -31,6 +31,10 @@ releases:
     projects:
       - repo: openstack/python-novaclient
         hash: 79959abc90bc615687e3a940951ad9ec548178ec
+  - version: train-em
+    projects:
+      - repo: openstack/python-novaclient
+        hash: 79959abc90bc615687e3a940951ad9ec548178ec
 branches:
   - name: stable/train
     location: 15.1.0