The repo is Python 3 now, so update hacking to version 3.0 which
supports Python 3.
Update local hacking check for new flake8 version.
Blacklist:
W504 line break after binary operator
Fix:
E741 ambiguous variable name
E117 over-indented
E305 expected 2 blank lines after class or function definition, found 1
F841 local variable 'e' is assigned to but never used
W605 invalid escape sequence '\.'
Change-Id: I99d574ca6569f1f177d2c5ce1011f269f4343619
7f638bb493