Update openSUSE installation instructions

Out of box, the 'sudo' command on openSUSE does not work similarly to other distros.  In this case, the path to usermod should be explicitly given, since /usr/sbin, where usermod is located, is not on the sudoing user's PATH.  The other sudo commands here should be fine.
Update libcontainer to db65c35051d05f3fb218a0e84a1

Signed-off-by: Michael Crosby <michael@docker.com>
Merge pull request #7634 from krrg/patch-1

Update openSUSE installation instructions
Merge pull request #7648 from crosbymichael/update-libcontainer-aug5

Update libcontainer to db65c35051d05f3fb218a0e84a1
Clean up typos in hub_registry_spec.md

Couple of instances of incorrect articles (e.g. "an Docker Hub").
Change default label of container volumes to shared SELinux Label

Since these will be shared between containers we want to label
them as svirt_sandbox_file_t:s0.  That will allow multiple containers
to write to them.

Currently we are allowing container domains to read/write all content in
/var/lib/docker because of container volumes.  This is a big security hole
in our SELinux story.

This patch will allow us to tighten up the security of docker containers.

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