Merge branch 'pw/rebase-reread-todo-after-editing'

The code to re-read the edited todo list in "git rebase -i" was
made more robust.

* pw/rebase-reread-todo-after-editing:
  rebase: fix todo-list rereading
  sequencer.c: factor out a function

diff --cc sequencer.c
Simple merge

diff --cc sequencer.h
Simple merge