Merge branch 'jh/send-email-one-cc' into maint

"Cc:" on the trailer part does not have to conform to RFC strictly,
unlike in the e-mail header.  "git send-email" has been updated to
ignore anything after '>' when picking addresses, to allow non-address
cruft like " # stable 4.4" after the address.

* jh/send-email-one-cc:
send-email: only allow one address per body tag

diff --cc git-send-email.perl
Simple merge

diff --cc t/t9001-send-email.sh
Simple merge