This is based on @brendar's instructions, which is based on email addresses from GitHub docs. It creates two labels:
GitHubGitHub - Important
Save the attached mailFilters.xml file locally, then in Gmail, go to Settings -> Filters and Blocked Addresses, then click on Import Filters, browse to the attached .xml file and click Open file. Then click the Create filters button if they look good.
- Filter all GitHub notifications out of the inbox and apply the
GitHublabel