pwcli: prefer git's sendemail.from config for emails
pwcli: prefer git's sendemail.from config for emails

It's possible to have a different email address for outgoing
email than the email address for patch signoffs, so account
for that and prefer sendemail.from over user.name/user.email
just like git send-email would do.

Signed-off-by: Johannes Berg <8398eb9892c5ab2ff439ca0b5e4b0706dd9ebef9@sipsolutions.net>

kvalo/pwcli,kvalo/pwcli