parse_mailboxes should probably eventually be completely equivalent to
Mail::Address, and if this happens we can drop the Mail::Address
dependency. Add a comment in the code reminding the current state of the
code, and point to the corresponding failing test to help future
contributors to get it right.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>