Updated the COPY directive reference: Source can't be a URL for COPY (+ formatting error fixes)

Signed-off-by: Roman Dudin <katrmr@gmail.com>
Fix: Failed Start breaks VolumesFrom

Running parseVolumesFromSpec on all VolumesFrom specs before initialize
any mounts endures that we don't leave container.Volumes in an
inconsistent (partially initialized) if one of out mount groups is not
available (e.g. the container we're trying to mount from does not
exist).

Keeping container.Volumes in a consistent state ensures that next time
we Start() the container, it'll run prepareVolumes() again.

The attached test demonstrates that when a container fails to start due
to a missing container specified in VolumesFrom, it "remembers" a Volume
that worked.

Fixes: #8726

Signed-off-by: Thomas Orozco <thomas@orozco.fr>
Add some details about the lifecycle of commands started with docker exec

Signed-off-by: Sven Dowideit <SvenDowideit@home.org.au>
Merge pull request #8726 from krallin/failed-start-breaks-volumes-from

Fix: a failed Start() breaks --volumes-from on subsequent Start()'s
pkg/archive: add interface for Untar

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
Cleanup some integration-cli output

I noticed a few things that were bugging me in the output
of the integration-cli tests.
- one of the tests used println to stdout so we had garage sent to the screen
- some of the test, in their final log message, didn't include the name of
  the group/file e.g.  daemon - run,iptables   was just   run,iptables

And yes, I noticed this because I'm anal :-)  but also because we should keep
the output of the tests as clean as possible so its easy to spot it when
things go bad.

Signed-off-by: Doug Davis <dug@us.ibm.com>
Merge pull request #9091 from duglin/CleanupIntTests

Cleanup some integration-cli output
Merge pull request #9082 from SvenDowideit/pr_out_add_some_details_about_the_lifecycle_of_commands_started_with_docker_exec

Add some details about the lifecycle of commands started with docker exec
Merge pull request #8840 from decadent/fix-da-copy-directive-reference

Nuh uh... quoth the build log: Source can't be a URL for COPY
Merge pull request #9090 from unclejack/archive_interface

pkg/archive: add interface for Untar
Allow IPC namespace to be shared between containers or with the host

Some workloads rely on IPC for communications with other processes.  We
would like to split workloads between two container but still allow them
to communicate though shared IPC.

This patch mimics the --net code to allow --ipc=host to not split off
the IPC Namespace.  ipc=container:CONTAINERID to share ipc between containers

If you share IPC between containers, then you need to make sure SELinux labels
match.

Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)