Special mode User APCs now documented

[Mathnerd314]

Hi, was reading your blog posts and noticed that QueueUserAPC2 is documented (as of Nov. 5):
https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-queueuserapc2

Other than that I wanted to bug you to finish the APC series. Thanks for what you've written so far!