Update hacking for Python3

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

Fix problems found.

Change-Id: I8fed95ecb736e0b6d7c4b63a55553de1539139be

Author: ajaeger

test-requirements.txt

@@ -2,7 +2,8 @@
 # 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,<3.1.0 # Apache-2.0
+
 # remove this pyflakes from here once you bump the
 # hacking to 3.2.0 or above. hacking 3.2.0 takes
 # care of pyflakes version compatibilty.

tox.ini

@@ -61,7 +61,7 @@ commands =
 # E123, E125 skipped as they are invalid PEP-8.
 
 show-source = True
-ignore = E123,E125
+ignore = E123,E125,W503,W504
 builtins = _
 exclude=.venv,.git,.tox,dist,doc,*lib/python*,*egg,build,releasenotes