move zuul config to repo

Currently this project has a number of generic templates defined in
it's job definition for project-config. These templates should be
defined at the project level; not global. This patch moves the
templates to the .zuul.yaml of this project.

Also see: https://review.openstack.org/#/c/652680/

Change-Id: Id53907dbb845b7c0f1d025ac5595b94335117a2a

.zuul.yaml

@@ -1,3 +1,6 @@
 - project:
     templates:
       - openstack-lower-constraints-jobs
+      - openstack-python-jobs-neutron
+      - openstack-python36-jobs
+      - check-requirements

setup.cfg

@@ -16,7 +16,7 @@ classifier =
     Programming Language :: Python :: 2
     Programming Language :: Python :: 2.7
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.5
+    Programming Language :: Python :: 3.6
 
 [files]
 packages =

tox.ini

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