Label relevant GitHub issues and pull requests with the "VIP" label

[wilfwilson]

I added a label called "VIP" that I think will be handy for making it easy to find those contributions made by VIPers.

Perhaps one of those keen VIPers would like to look through old open/closed PRs (especially PRs, but also issues if they're mega keen), and label any pull requests made by students during their VIP times. 🙂