Add py37 and API v2 jobs (scenario, tempest)

Run also:
- the API v2 scenario and tempest tests
- the py37 tests
on both the check
and the gate queue.
No need to set LIBS_FROM_GIT anymore, Zuul sets it automatically
for projects listed under request-projects.

The addition of py37 implements the following task:
Story: 2004073
Task: 27450
Change-Id: I4ff72efa0af76bd2e710e9c1be4d77fd6af83582

.zuul.yaml

@@ -5,6 +5,7 @@
       - openstack-python-jobs
       - openstack-python35-jobs
       - openstack-python36-jobs
+      - openstack-python37-jobs
       - publish-openstack-docs-pti
       - check-requirements
       - release-notes-jobs-python3
@@ -12,12 +13,16 @@
     check:
       jobs:
         - python-saharaclient-scenario
+        - python-saharaclient-scenario-v2
         - python-saharaclient-tempest
+        - python-saharaclient-tempest-v2
     gate:
       queue: sahara
       jobs:
         - python-saharaclient-scenario
+        - python-saharaclient-scenario-v2
         - python-saharaclient-tempest
+        - python-saharaclient-tempest-v2
     experimental:
       jobs:
         - openstack-tox-pypy
@@ -25,13 +30,20 @@
 - job:
     name: python-saharaclient-scenario
     description: |
-      Run scenario tests for Sahara against python-saharaclient changes.
+      Run scenario tests for Sahara against python-saharaclient
+      changes.
     parent: sahara-tests-scenario
     required-projects:
       - openstack/python-saharaclient
-    vars:
-      devstack_localrc:
-        LIBS_FROM_GIT: python-saharaclient
+
+- job:
+    name: python-saharaclient-scenario-v2
+    description: |
+      Run scenario tests for Sahara on API v2 against python-saharaclient
+      changes.
+    parent: sahara-tests-scenario-v2
+    required-projects:
+      - openstack/python-saharaclient
 
 - job:
     name: python-saharaclient-tempest
@@ -41,6 +53,12 @@
     parent: sahara-tests-tempest
     required-projects:
       - openstack/python-saharaclient
-    vars:
-      devstack_localrc:
-        LIBS_FROM_GIT: python-saharaclient
+
+- job:
+    name: python-saharaclient-tempest-v2
+    description: |
+      Run Tempest tests from the Sahara plugin on API v2 against
+      python-saharaclient changes.
+    parent: sahara-tests-tempest-v2
+    required-projects:
+      - openstack/python-saharaclient

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py27,py35,py36,pypy,pep8,releasenotes
+envlist = py27,py35,py36,py37,pypy,pep8,releasenotes
 minversion = 2.0
 skipsdist = True