- use the six version of configparser and urllib, and depends on six;
- remove relative imports;
- adapt few tests to the changes.
The changes above should be noop from the point of view of
functionalities, at least on python 2.
And also:
- replace the py34 tox virtualenv with py35;
- add a non-voting py35 job (locally for now, it will be enabled
to project-config also for gating when stable).
Story: 2002574
Task: 22142
Change-Id: I0a35abaae6f5b7095ebae765fbe2163046e0a4da
cdbc98572d