FUTURE: Checks under neverSuppressedChecks group should give more precise violations

[rdiachenko]

Currently, all violations from the checks under neverSuppressedChecks group will be shown, even though the code isn't changed. Investigate checks marked with that property and try to come up with more precise strategies for them. Ideally, if code was changed and that change leads to a new violation that violation should be shown only.