Merge branch 'lo/mv-missing-dest-dir-check'

Merge branch 'lo/mv-missing-dest-dir-check'

'git mv' has been updated to check for a missing destination
leading directory during the checking phase, allowing 'git mv -n'
to report the failure.  The error message when the rename(2)
syscall fails has also been improved to name both the source and
the destination.

* lo/mv-missing-dest-dir-check:
  mv: reject a destination whose leading path is missing or a symlink
  mv: name both source and destination when rename fails