[MlMt] Installing gpg2 via homebrew?

[leo]

Sorry I send this message as a — totally off-topic — thread reply. 
Here again with its own proper subject:

I just switched the MailMate list delivery to digest – and now I get 
in MailMate a complaint about `gpg2` which I do not have installed.

The Help pages say I should install it via the GPGTools, but whenever 
possible I try to install command line tools via 
[Homebrew](https://brew.sh/). `brew` lists a gpg2 formula as installable 
– is this save to use for MailMate? Do I have to hint to MailMate 
somehow where the tool is installed?