Blueprints: Allow for gist.github.com instead of gist.githubusercontent.com

[bph]

It was a great enhancement to allow for normal GitHub URLs to be used in blueprints.

https://github.com/WordPress/blueprints/blob/trunk/blueprints/custom-post/books.php

Instead of

https://raw.githubusercontent.com/WordPress/blueprints/blob/trunk/blueprints/custom-post/books.php

Now it would be consistent if that would also work for content in GitHub Gists:

Use:
https://gist.github.com/ndiego/456b74b243d86c97cda89264c68cbdee

instead of
https://gist.githubusercontent.com/ndiego/456b74b243d86c97cda89264c68cbdee/raw/ff00cf25e6eebe4f5a4eaecff10286f71e65340b/block-hooks-demo.php

It not only would decrease mental load when writing blueprints, it would also make blueprints much more readable.