Link to GitHub issues, pull requests, commits and users for a particular project.

To use this extension, add it to the extensions list in conf.py, and set the variable github_project_url:

extensions = [...
              'sphinxcontrib_github_alt',
             ]

github_project_url = "https://github.com/ipython/ipython"

Then use these roles in your documentation:

* :ghissue:`12` - link to issue #12
* :ghpull:`35` - link to pull request #35
* :ghcommit:`3a1cb54` - link to commit
* :ghuser:`ipython` - link to a user or organisation

It's called 'alt' because sphinxcontrib-github already exists. IPython & Jupyter projects have been using the syntax defined in this extension for some time before we made it into its own package, so we didn't want to switch to sphinxcontrib-github.