Merge branch 'en/merge-ort-recursive'

The ORT merge strategy learned to synthesize virtual ancestor tree by recursively merging multiple merge bases together, just like the recursive backend has done for years. * en/merge-ort-recursive: merge-ort: implement merge_incore_recursive() merge-ort: make clear_internal_opts() aware of partial clearing merge-ort: copy a few small helper functions from merge-recursive.c commit: move reverse_commit_list() from merge-recursive