Merge branch 'js/patch'

* js/patch:
  diff.c: fix get_patch_id()
  t4014: fix test commit labels.
  format-patch: use clear_commit_marks() instead of some ad-hockery
  t4014: fix for whitespace from "wc -l"
  t4014: add format-patch --ignore-if-in-upstream test
  format-patch: introduce "--ignore-if-in-upstream"
  add diff_flush_patch_id() to calculate the patch id