Merge branch 'ds/add-with-sparse-index'

"git add" can work better with the sparse index.

* ds/add-with-sparse-index:
  add: remove ensure_full_index() with --renormalize
  add: ignore outside the sparse-checkout in refresh()
  pathspec: stop calling ensure_full_index
  add: allow operating on a sparse-only index
  t1092: test merge conflicts outside cone

diff --cc builtin/add.c
Simple merge