So far after Googleing for a while and with the help of the IRC I've found this: http://stackoverflow.com/a/6235394/1622940

It covers well the difference between a Git pull request and a GitHub pull request. It also makes it clear how to make a pull request outside of GitHub.

It says the command makes output appropriate for a mailing list or something of the sort, so this means it could be put in a text file as an attachment or something of the sort.

Now to figure out how one merges this pull request...