Dropping the py35 testing

All the integration testing has been moved to
Bionic now[1] and py3.5 is not tested runtime for
Train or stable/stein[2].

As per below ML thread, we are good to drop the py35
testing now:
http://lists.openstack.org/pipermail/openstack-discuss/2019-April/005097.html

[1] http://lists.openstack.org/pipermail/openstack-discuss/2019-April/004647.html
[2]
https://governance.openstack.org/tc/reference/runtimes/stein.html
https://governance.openstack.org/tc/reference/runtimes/train.html

Change-Id: I09222df09e6c6618a06a08479638be3953e19ed4

.zuul.yaml

@@ -195,7 +195,6 @@
       - openstack-python36-jobs
       - openstack-python37-jobs
       - openstack-python-jobs
-      - openstack-python35-jobs
       - check-requirements
       - publish-openstack-docs-pti
       - release-notes-jobs-python3
@@ -207,7 +206,6 @@
         - patrole-member-rocky
         - patrole-member-queens
         - patrole-member-pike
-        - patrole-py35-member
         - patrole-multinode-admin
         - patrole-multinode-member
         - patrole-extension-admin

setup.cfg

@@ -16,8 +16,7 @@ classifier =
     Programming Language :: Python :: 2
     Programming Language :: Python :: 2.7
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.3
-    Programming Language :: Python :: 3.5
+    Programming Language :: Python :: 3.6
 
 [files]
 packages =

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 minversion = 2.0
-envlist = pep8,py35,py36,py37,py27
+envlist = pep8,py36,py37,py27
 skipsdist = True
 
 [testenv]