Since `dirperm1` requires a more recent aufs patch than many current OS release,
we cant remove #783 completely. This documents that docker will apply `dirperm1`
automatically for systems that support it
Signed-off-by: Daniel, Dao Quang Minh <dqminh89@gmail.com>
Upstream-commit: d7bbe2fcb5bf44f2fbcfa472e2a06c83d5d3aca1
Component: engine