fix(CONTRIBUTING): Developer Certificate of Origin w/o Grant

In 7fb55f77250a9b52b0515a7e655ecc605ae452ca the DCO lost the grant so
change the title back to just DCO.

Docker-DCO-1.1-Signed-off-by: Brandon Philips <brandon.philips@coreos.com> (github: philips)
Adjust test to match its comment

Docker-DCO-1.1-Signed-off-by: Andrew Williams <williams.andrew@gmail.com> (github: TheDude05)
Remove unused reflink files
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Move proxy into pkg
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Move volumes out of container.go and into volumes.go

This helps clean up the container file and move volumes into
one location.  We currently cannot move volumes to a sub pkg
because they depend on Container and also modify fields on the
container.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Remove container dependency for links
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Move links to sub pkg
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Fix engine tests on systems where temp directories are symlinked.

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
Document Darwin test failure in a FIXME

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
Add socket activation for go apps
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Use socket activation pkg for listeners
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Integration generic socket wait for docker api
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Change name to listenbuffer
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
`docker cp` error when container doesn't exist

Fix cp api to return a 404 notfound if container doesn't exist.
Fixes #4119.

Docker-DCO-1.1-Signed-off-by: Fabio Falci <fabiofalci@gmail.com> (github: fabiofalci)
Test for save and load commands

Improve test for save to tar and load from tar commands.
Docker-DCO-1.1-Signed-off-by: Fabio Falci <fabiofalci@gmail.com> (github: fabiofalci)
Add dockerode NodeJS implementation
Also correctly case 'JavaScript'

Docker-DCO-1.1-Signed-off-by: Mike MacCana <mike.maccana@gmail.com> (github: mikemaccana)
Avoid temporarily unmounting the container when restarting it

Stopping the container will typicall cause it to unmount, to keep it mounted
over the stop/start cycle we aquire a temporary reference to it during this time.

This helps with https://github.com/dotcloud/docker/issues/4036

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
Merge pull request #4061 from mikemaccana/patch-1

Add dockerode NodeJS implementation
Add vendored archive/tar that includes xattrs patch

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Merge pull request #4164 from fabiofalci/cp_error_message

`docker cp` error when container doesn't exist