Update hacking for Python3

The repo is Python 3 now, so update hacking to version 3.0 which
supports Python 3.

Update local hacking checks for new flake8.

Remove hacking and friends from lower-constraints, they are not needed
for installation.

Change-Id: Ib6f30427e736ff488598e80e87ce0a8b39e92f33

lower-constraints.txt

@@ -26,11 +26,8 @@ eventlet==0.18.2
 extras==1.0.0
 fasteners==0.7.0
 fixtures==3.0.0
-flake8==2.5.5
-flake8-import-order==0.12
 futurist==1.2.0
 greenlet==0.4.10
-hacking==1.1.0
 horizon==18.3.1
 idna==2.6
 iso8601==0.1.11
@@ -69,7 +66,6 @@ osprofiler==2.3.0
 Paste==2.0.2
 PasteDeploy==1.5.0
 pbr==2.0.0
-pep8==1.5.7
 pika==0.10.0
 pika-pool==0.1.3
 Pint==0.5
@@ -77,7 +73,6 @@ positional==1.2.1
 prettytable==0.7.2
 pycodestyle==2.3.1
 pycparser==2.18
-pyflakes==0.8.1
 pyinotify==0.9.6
 pymongo==3.0.2
 pyOpenSSL==17.1.0

test-requirements.txt

@@ -7,7 +7,7 @@
 # be installed in a specific order.
 #
 # Hacking should appear first in case something else depends on pep8
-hacking>=1.1.0,<1.2.0 # Apache-2.0
+hacking>=3.0,<3.1.0 # Apache-2.0
 #
 coverage!=4.4,>=4.0 # Apache-2.0
 doc8>=0.6.0 # Apache-2.0

tox.ini

@@ -64,10 +64,6 @@ deps = -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/
        -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
-# Temporary disabled to pass the pep8 job
-# [hacking]
-# local-check-factory = horizon.hacking.checks.factory
-
 [flake8]
 exclude = .venv,.git,.tox,dist,*lib/python*,*egg,build,panel_template,dash_template,local_settings.py,*/local/*,*/test/test_plugins/*,.ropeproject,node_modules,.tmp
 # F405 TEMPLATES may be undefined, or defined from star imports
@@ -79,6 +75,10 @@ ignore = F405,W504
 max-complexity = 20
 import-order-style = pep8
 
+[flake8:local-plugins]
+extension =
+  M322 = horizon.hacking.checks:no_mutable_default_args
+
 [testenv:npm]
 passenv =
   HOME