Merge branch 'jc/read-tree-df'

* jc/read-tree-df:
  t3030: merge-recursive backend test.
  merge-recursive: handle D/F conflict case more carefully.
  merge-recursive: do not barf on "to be removed" entries.
  Treat D/F conflict entry more carefully in unpack-trees.c::threeway_merge()
  t1000: fix case table.