[GNC] Documentation changes needed

[john]

> On May 11, 2022, at 8:30 AM, Phillip Duff <phil.duff7 at gmail.com> wrote:
> 
> (Needs to have added here for Mac users that if you install XTools, you already have both Git and make (which ic buried further down, too late). We should simply recommend that Xtools is installed, whether it is 4Gb is irrelevant in today’s world generally, and we should move away from command line wherever possible for documenters.

I think you mean Xcode that is indeed enormous. There's a smaller alternative for command line work called "the command line developer tools". You can install that directly with `Xcode-select --install` but since MacOS X 10.11 (El Capitan) or so there are stubs for the included commands that pop up a dialog box asking if you want to install them, so just type `git` at a terminal prompt and click OK.

Regards,
John Ralls