Merge branch 'rr/revert-cherry-pick'

* rr/revert-cherry-pick:
t3502, t3510: clarify cherry-pick -m failure
t3510 (cherry-pick-sequencer): use exit status
revert: simplify getting commit subject in format_todo()
revert: tolerate extra spaces, tabs in insn sheet
revert: make commit subjects in insn sheet optional
revert: free msg in format_todo()

diff --cc builtin/revert.c
Simple merge