[bug#45957] learning git-send-email is interesting

[Joshua Branson]

Thanks for the edit suggestions.  I appreciated learning about (inherit ) 
procedure.  That is super helpful!  Here's an updated commit. Thanks for
your timely responses in helping me merge this to the cookbook!

Let me know if this "intro" section makes it hard for you to merge this
patch.  I just learning about --compose from git-send-email 5 minutes
ago.