Merge branch 'en/merge-ort-prepare-to-remove-recursive'

Merge branch 'en/merge-ort-prepare-to-remove-recursive'

First step of deprecating and removing merge-recursive.

* en/merge-ort-prepare-to-remove-recursive:
  am: switch from merge_recursive_generic() to merge_ort_generic()
  merge-ort: fix merge.directoryRenames=false
  t3650: document bug when directory renames are turned off
  merge-ort: support having merge verbosity be set to 0
  merge-ort: allow rename detection to be disabled
  merge-ort: add new merge_ort_generic() function