Merge branch 'js/rebase'

* js/rebase:
  Teach rebase -i about --preserve-merges
  rebase -i: provide reasonable reflog for the rebased branch
  rebase -i: several cleanups
  ignore git-rebase--interactive
  Teach rebase an interactive mode
  Move the pick_author code to git-sh-setup

diff --cc Makefile
Simple merge

diff --cc git-sh-setup.sh
Simple merge