All tools modev to tox.

* pep8 + copy-pasted hacking.py + pyflakes are replaced with flake8 + hacking;
* pylint and docs envs are added to tox;
* all tools are now links to tox.

Change-Id: I142a1d3f9c80dab4bf145890bb066c86b7a9c376
Fixed: bug #1169032