updated d235j-xbox360-controller-driver.rb to stable
Remove homebrew-fork Checksum class and refactor

* perform actual checksum calculation within download.rb
* use an accessor named sha256 instead of sums for checksum data
* migrate checksum-specific exceptions out of homebrew-fork
remove homebrew-fork extend/string.rb

Integrate the last remaining monkeypatch `undent` into our own codebase.
Merge pull request #8386 from vitorgalvao/update-d235j-xbox360-controller-driver

updated d235j-xbox360-controller-driver.rb to stable
Merge pull request #8392 from rolandwalker/remove_homebrew_extend_string

remove homebrew-fork extend/string.rb
Merge pull request #8388 from rolandwalker/remove_homebrew_checksum

Remove homebrew-fork `Checksum` class and refactor
rm some unused methods from homebrew-fork mac.rb