Revert "Revert PR #621"

This reverts commit d32db58bb3f693de33776229c76185d270d32a6e.
Allow non relative imports for now (W0403).
Revert "W0403: Honour relative imports."

Conflicts:
	features/environment.py

Conflicts due to util.setup_db already dropped as empty import.
Do not cancel entire checksuite if pylint is absent.
Merge pull request #641 from Renelvon/pylint_checks

Pylint is back for good