GitLab

The detailed info per renamed directory is stored in a regular file per
branch, ie. when each of two lower branches contains the same named
entry, then the created info files will be two.
The file is created internally by aufs rename(2) and loaded by lookup.
Also when the actual rename on the branch fails, the newly created or
stored info file should be all reverted.

When the renamed dir is renamed-back to the previous/original name, then
the info file has to be removed.
Signed-off-by: J. R. Okajima <hooanon05g@gmail.com>