This is a simple Chrome extension to ignore those pesky diffs you just don't care to see in a Github pull request. Great for when you add external JS libraries and don't want to see that code.
Add's a button to toggle visibility of files.
- Chrome Web Store: https://chrome.google.com/webstore/detail/github-collapse-diff/eenmpdlgpfhmgkkmpjmmchokkmjacaeo
- Userscripts.org: http://userscripts.org/scripts/show/171337