* finished #6925
* augmented per @BrennanConroy
* fixed css link
* added method to hub
* added code from sample to file
* fixed user sample
* removed the email version of this sample
* removed last mention of the customization
* Minor edits
Addresses #8579
I might be getting the hang of **_find and replace_** now. 😝
This doesn't touch a couple that ref 2.2.0. I'll tidy those up on https://github.com/aspnet/Docs/issues/8518 after 2.2 RTM.