improve path cleaner - Githubissues

This PR fixes and improves Rubocop::PathCleanup.

It's now possible to cleanup global command patterns (i.e. bin/**/*)
It removes the Include: or Exclude: property if all entries have been removed
It removes the entire Cop if no properties are left due to cleanup
It adds more test cases
It adds the CLI option --preserve-paths if cleanup is not wanted

lxxxvi / ruboclean