@engelke Would you be able to review this?

Seems to be a problem with nox under Python 2.7, which Travis is using for lint. Here's the error message:

Traceback (most recent call last):
File "/home/travis/virtualenv/python2.7.14/bin/nox", line 7, in
from nox.main import main
File "/home/travis/virtualenv/python2.7.14/lib/python2.7/site-packages/nox/main.py", line 155
print(dist.version, file=sys.stderr)
^
SyntaxError: invalid syntax

Changes were moved to PR 1770 in order to add broader changes needed to pass Travis check.