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 allows us to mimic the --net code to allow --ipc=host to not split off
the IPC Namespace.  ipc=container:CONTAINERID to share ipc between containers

Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
Only fetch network stats we use.

The dynamic version using WalkPath() was expensive and we only used some
of the stats anyways.

Signed-off-by: Victor Marmol <vmarmol@google.com>
Merge pull request #244 from vmarmol/net-stats

Only fetch network stats we use.
Merge branch 'unreserve' of https://github.com/rhatdan/libcontainer into rhatdan-unreserve
Add test for IPC host sharing

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Add test for ipc private and shared path

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Merge pull request #245 from crosbymichael/share-ipc

Allow IPC namespace to be shared between containers or with the host
Mount /dev/mqueue by default

Need this for supporting Posix Message Queues

man mq_overview

Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
Merge pull request #246 from rhatdan/mqueue

Mount /dev/mqueue by default
Add ContainerInfo instead of using a readonly state

This modifies Load in the factory to return a ContainerInfo interface
that is the read only view of the container when it is loaded.

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Update container interface with process operations

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Implement linux factory and container with readonly interface

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Add stacktrace package for collection of stacktraces

This helps aid our effort of returning useful errors.

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Add testing for linux factory Load

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Add cgroup manage for mocking of package resources

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Remove ContainerInfo interface

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>