Add job to propose tag merges

With pbr tag-based versioning, not having the latest release tag in the
master branch makes the output a little nasty. Add a job that makes a
merge commit containing the tag on a release from milestone-proposed
branch. The merge strategy it uses is 'ours' because we're not
attempting to use this to keep code lines up to date - the expectation
is that content added in milestone-proposed should already be in master.
The main thing we want to do is re-connect the revision and tag history
with master, so that things like 'git tag --contains' work.

Closes-Bug: 1192039
Change-Id: I06c06bd7542ae493e74fdcaa3c4419f84843cd03

modules/jenkins/files/slave_scripts/merge_tags.sh

@@ -0,0 +1,27 @@
+#!/bin/bash -xe
+
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+TAG=$1
+
+git config user.name "OpenStack Jenkins"
+git config user.email "jenkins@openstack.org"
+git config gitreview.username "jenkins"
+
+git review -s
+git checkout master
+git reset --hard origin/master
+git merge -s ours $TAG
+# Get a Change-Id
+GIT_EDITOR=true git commit --amend
+git review -R -t merge/release-tag

modules/openstack_project/files/jenkins_job_builder/config/openstack-publish-jobs.yaml

@@ -18,7 +18,25 @@
       - console-log
 
 
+- job-template:
+    name: '{name}-merge-release-tags'
+    concurrent: false
+
+    builders:
+      - gerrit-git-prep
+      - shell: |
+          #!/bin/bash -xe
+          TAG=`echo $ZUUL_REFNAME | sed 's/refs.tags.//'`
+          /usr/local/jenkins/slave_scripts/merge_tags.sh $TAG
+
+    publishers:
+      - console-log
+
+    node: 'proposal'
+
+
 - job-group:
     name: openstack-publish-jobs
     jobs:
       - '{name}-docs'
+      - '{name}-merge-release-tags'

modules/openstack_project/files/zuul/layout.yaml

@@ -228,6 +228,8 @@ jobs:
     branch: ^(?!stable/(folsom|grizzly)).*$
   - name: manuals-upstream-translation-update
     branch: ^master$
+  - name: ^.*-merge-release-tags$
+    branch: milestone-proposed
   - name: gate-hacking-python33
     voting: false
   - name: gate-hacking-integration-nova
@@ -606,6 +608,7 @@ projects:
     release:
       - cinder-tarball
       - cinder-docs
+      - cinder-merge-release-tags
     periodic:
       - cinder-propose-translation-update
       - periodic-cinder-docs-stable-grizzly
@@ -649,6 +652,7 @@ projects:
     release:
       - glance-tarball
       - glance-docs
+      - glance-merge-release-tags
     periodic:
       - glance-propose-translation-update
       - periodic-glance-docs-stable-folsom
@@ -699,6 +703,7 @@ projects:
     release:
       - horizon-tarball
       - horizon-docs
+      - horizon-merge-release-tags
     periodic:
       - periodic-horizon-docs-stable-folsom
       - periodic-horizon-python26-stable-folsom
@@ -770,6 +775,7 @@ projects:
     release:
       - keystone-tarball
       - keystone-docs
+      - keystone-merge-release-tags
     periodic:
       - keystone-propose-translation-update
       - periodic-keystone-docs-stable-folsom
@@ -821,6 +827,7 @@ projects:
     release:
       - nova-tarball
       - nova-docs
+      - nova-merge-release-tags
     periodic:
       - nova-propose-translation-update
       - periodic-nova-docs-stable-folsom
@@ -961,6 +968,7 @@ projects:
     release:
       - neutron-tarball
       - neutron-docs
+      - neutron-merge-release-tags
     periodic:
       - neutron-propose-translation-update
       - periodic-neutron-docs-stable-grizzly
@@ -1006,6 +1014,7 @@ projects:
     release:
       - swift-tarball
       - swift-docs
+      - swift-merge-release-tags
 
   - name: openstack/python-ceilometerclient
     check:
@@ -1558,6 +1567,7 @@ projects:
     release:
       - ceilometer-docs
       - ceilometer-tarball
+      - ceilometer-merge-release-tags
     periodic:
       - ceilometer-propose-translation-update
       - periodic-ceilometer-docs-stable-grizzly
@@ -1639,6 +1649,7 @@ projects:
     release:
       - heat-tarball
       - heat-docs
+      - heat-merge-release-tags
     periodic:
       - periodic-heat-docs-stable-grizzly
       - periodic-heat-python26-stable-grizzly
@@ -1743,6 +1754,7 @@ projects:
     release:
       - trove-tarball
       - trove-docs
+      - trove-merge-release-tags
 
   - name: openstack/trove-integration
     check:
@@ -2820,6 +2832,7 @@ projects:
     release:
       - ironic-tarball
       - ironic-docs
+      - ironic-merge-release-tags
 
   - name: openstack/python-ironicclient
     check: