Documentation: add a bit about sendemail.to configuration
Documentation: add a bit about sendemail.to configuration

While there is information about this in the configuration section, it was
missing in the options section.

Signed-off-by: Mike Hommey <9904419133015298990973ad253a390ae1d3133a@glandium.org>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git