[MlMt] MailMate needs to be updated warning

[John Cooper]

Benny Kjær Nielsen wrote (at 1:37 AM on Saturday, Apr 9, 2022):

> This means `emate` still doesn't work in the latest test release (for most users on macOS 12.3). Instead, I should complete my work on a replacement for `emate`. No time frame on that though.

Assuming that emate is something I'd want to help make MailMate fully functional, what's the simplest way to make it so? I don't have the full Xcode package installed, but I have installed the Xcode command-line tools, and homebrew.