tl;dr: Copy the q42:accounts-microsoft and q42:microsoft package, modify the URLs and service name and it works! Probably anyway...
When creating a commercial application with a wide target audience, you can stumble upon users wanting to login using an unknown and barely used OAuth service. And why deny your users this when you can easily create a login service package?
With only about 400 million active users and only 2nd place as world most valuable brand it makes sense that no developer has created an implementation to log in with your Microsoft account. But believe it or not, some people like logging in with their Microsoft Account. And so, by building on the the default meteor google and [accounts-google](https://atmospherejs.com/me