Merge branch 'mm/send-email-fallback-to-local-mail-address'

Instead of maintaining home-grown email address parsing code, ship
a copy of reasonably recent Mail::Address to be used as a fallback
in 'git send-email' when the platform lacks it.

* mm/send-email-fallback-to-local-mail-address:
  send-email: add test for Linux's get_maintainer.pl
  perl/Git: remove now useless email-address parsing code
  send-email: add and use a local copy of Mail::Address