Unify inclusion/exclusion params names

They were Includes/Excludes for AllCops, but Include/Exclude for
individual cops. Now they are Include/Exclude everywhere for sanity's sake.
[Fix #888] Require only the powerpack extensions that we actually need
Add auto-correction to StringConversionInInterpolation cop
Extract NonNilCheck cop from NilComparison
Fix offenses reported by NonNilCheck
Add auto-correction to NilComparison cop
Simplify a bit NilComparison
add disabled_lines_formatter

implement yujinakayama's suggested changes