Merge branch 'bc/rev-parse-parseopt-fix' into next

Recent versions of "git rev-parse --parseopt" did not parse the
option specification that does not have the optional flags (*=?!)
correctly, which has been corrected.

* bc/rev-parse-parseopt-fix:
git-rebase: don't ignore unexpected command line arguments
rev-parse parseopt: interpret any whitespace as start of help text
rev-parse parseopt: do not search help text for flag chars
t1502: demonstrate rev-parse --parseopt option mis-parsing

diff --cc builtin/rev-parse.c
Simple merge

diff --cc git-rebase.sh
Simple merge