Cleanup py27 support

This repo is now testing only with Python 3, so let's make
a few cleanups:
- Remove python 2.7 stanza from setup.py
- Remove obsolete sections from setup.cfg
- Update classifiers
- Remove install_command from tox.ini, the default is fine
- Stop py35 testing, OpenStack has py36 as minimal version

Change-Id: Iee8ffab15e11afe417f7369d907491b62ba063fb

.zuul.yaml

@@ -1,6 +1,5 @@
 - project:
     templates:
-      - openstack-python35-jobs
       - openstack-python36-jobs
     check:
       jobs:

setup.cfg

@@ -12,17 +12,15 @@ classifier =
     License :: OSI Approved :: Apache Software License
     Operating System :: OS Independent
     Programming Language :: Python
+    Programming Language :: Python :: Implementation :: CPython
+    Programming Language :: Python :: 3 :: Only
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.5
+    Programming Language :: Python :: 3.6
 
 [files]
 packages =
     goal_tools
 
-[global]
-setup-hooks =
-    pbr.hooks.setup_hook
-
 [entry_points]
 console_scripts =
     import-goal = goal_tools.import_goal:main
@@ -66,6 +64,3 @@ python3_first =
     tox fix = goal_tools.python3_first.toxsettings:ToxFixMissingPy3
 	wheel missing = goal_tools.python3_first.wheelsettings:WheelMissingUniversal
 	#wheel fix = goal_tools.python3_first.wheelsettings:WheelFixMissingUniversal
-
-[wheel]
-universal = 1

setup.py

@@ -13,17 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# THIS FILE IS MANAGED BY THE GLOBAL REQUIREMENTS REPO - DO NOT EDIT
 import setuptools
 
-# In python < 2.7.4, a lazy loading of package `pbr` will break
-# setuptools if some other modules registered functions in `atexit`.
-# solution from: http://bugs.python.org/issue15881#msg170215
-try:
-    import multiprocessing  # noqa
-except ImportError:
-    pass
-
 setuptools.setup(
     setup_requires=['pbr>=2.0.0'],
     pbr=True)

tox.ini

@@ -4,7 +4,6 @@ envlist = py36,pep8
 
 [testenv]
 basepython = python3
-install_command = pip install {opts} {packages}
 usedevelop = True
 deps =
   -r{toxinidir}/requirements.txt