t / t5100 / msg0018--no-inbody-headerson commit status: add --[no-]ahead-behind to status and commit for V2 format. (fd9b544)
   1From: Another Thor
   2 <a.thor@example.com>
   3Subject: This one contains
   4        a tab
   5 and a space
   6
   7a commit message
   8