Version bump to 2.7.4
Publish 2.7.4 Changelog
Merge branch 'recovered_commits'
whitespace
dependency has been renamed

In
https://github.com/bbatsov/rubocop/commit/ff167d8f202baf7a68955db0aaf0dc29afb7e7ee
the Rubocop class was renamed to RuboCop with no backwards compat
handling.