Add YAML linting in check and gate

Introduce YAML linting for check and gate queues so that
we don't introduce incorrect YAML in proposed changes.

Includes a couple of nit fixes so that tests actually pass.

Change-Id: Ie07f11a24fb2ad853b49b69fe295bcae2c5764e6

.gitignore

@@ -0,0 +1 @@
+.tox

.zuul.yaml

@@ -1,3 +1,7 @@
 - project:
-    templates:
-      - noop-jobs
+    check:
+      jobs:
+        - openstack-tox-validate
+    gate:
+      jobs:
+        - openstack-tox-validate

deployment_tools.yaml

@@ -78,7 +78,7 @@ tabs:
             docs-title: Docs
             docs-url: https://docs.openstack.org/openstack-chef/latest/
             download-title: Find OpenStack Charms in the Charm Store
-            download-url: https://jujucharms.com/openstack 
+            download-url: https://jujucharms.com/openstack
             desc: >
               Collection of Charms to deploy OpenStack using
               the Juju framework.

openstack_components.yaml

@@ -548,9 +548,10 @@ tabs:
                 expect to see from the project in the upcoming release.
               title: Horizon - Project Update
             support-teams:
-               i18n: https://governance.openstack.org/tc/reference/projects/i18n.html
-               documentation:
-                 https://governance.openstack.org/tc/reference/projects/documentation.html
+              i18n:
+                https://governance.openstack.org/tc/reference/projects/i18n.html
+              documentation:
+                https://governance.openstack.org/tc/reference/projects/documentation.html
 
   - name: Operations services
     map-bucket: openstack-operations
@@ -742,7 +743,7 @@ tabs:
             docs-url: https://docs.openstack.org/kuryr/latest/
             desc: >
               Bridge between containers frameworks networking models to
-              OpenStack networking abstraction 
+              OpenStack networking abstraction
             project-team: kuryr
             dependencies:
               - neutron

tox.ini

@@ -0,0 +1,15 @@
+[tox]
+envlist = validate
+minversion = 1.6
+skipsdist = True
+
+[testenv]
+install_command = pip install -U {opts} {packages}
+
+[testenv:validate]
+basepython = python3
+deps =
+    yamllint==1.4.1
+commands =
+    yamllint -f parsable \
+      deployment_tools.yaml openstack_components.yaml sdks.yaml