Cleanup py27 support

This repo is now testing only with Python 3, so let's make
a few cleanups:
- Remove python 2.7.3 stanza from setup.py
- Remove obsolete sections from setup.cfg
- Remove install_command from tox.ini, the default is fine
- Switch to hacking 3.0, ignore W503 and W504 (as in cinder repo)
- Use TOX_CONSTRAINTS instead of obsolete UPPER_CONSTRAINTS

Change-Id: Ia623c8af7f03c25bce7e4600693a7e834ab70000
diff --git a/setup.cfg b/setup.cfg
index 3ee7468..9b05085 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -21,29 +21,6 @@
 packages =
     cinder_tempest_plugin
 
-[build_sphinx]
-all-files = 1
-warning-is-error = 1
-source-dir = doc/source
-build-dir = doc/build
-
-[upload_sphinx]
-upload-dir = doc/build/html
-
-[compile_catalog]
-directory = cinder_tempest_plugin/locale
-domain = cinder_tempest_plugin
-
-[update_catalog]
-domain = cinder_tempest_plugin
-output_dir = cinder_tempest_plugin/locale
-input_file = cinder_tempest_plugin/locale/cinder_tempest_plugin.pot
-
-[extract_messages]
-keywords = _ gettext ngettext l_ lazy_gettext
-mapping_file = babel.cfg
-output_file = cinder_tempest_plugin/locale/cinder_tempest_plugin.pot
-
 [entry_points]
 tempest.test_plugins =
     cinder_tests = cinder_tempest_plugin.plugin:CinderTempestPlugin
diff --git a/setup.py b/setup.py
index 566d844..cd35c3c 100644
--- a/setup.py
+++ b/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)
diff --git a/test-requirements.txt b/test-requirements.txt
index af89592..bd50458 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -2,7 +2,7 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
+hacking>=3.0,<3.1 # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 python-subunit>=1.0.0 # Apache-2.0/BSD
diff --git a/tox.ini b/tox.ini
index 4c2edbc..be122b4 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,11 +9,10 @@
 [testenv]
 basepython = python3
 usedevelop = True
-install_command = pip install {opts} {packages}
 setenv =
    VIRTUAL_ENV={envdir}
    PYTHONWARNINGS=default::DeprecationWarning
-deps = -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+deps = -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
        -r{toxinidir}/test-requirements.txt
 commands = python setup.py test --slowest --testr-args='{posargs}'
 
@@ -25,8 +24,9 @@
 
 [flake8]
 # E123, E125 skipped as they are invalid PEP-8.
-
+# W503 line break before binary operator
+# W504 line break after binary operator
 show-source = True
-ignore = E123,E125
+ignore = E123,E125,W503,W504
 builtins = _
 exclude=.venv,.git,.tox,dist,doc,*lib/python*,*egg,build