Fixes #3879 by updating embedding of ascii.io (now asciinema.io)
Docker-DCO-1.1-Signed-off-by: Andy Rothfusz <github@developersupport.net> (github: metalivedev)
Move UserLookup functionality into a separate pkg/user submodule that implements proper parsing of /etc/passwd and /etc/group, and use that to add support for "docker run -u user:group" and for getting supplementary groups (if ":group" is not specified)

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Use type switch instead of reflection

Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Consolidate a bunch of the supplementary-groups tests to cut down on the number of RUN lines in a single Dockerfile within TestBuild

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
docker: detect defaultNetworkMtu from default route

Docker-DCO-1.1-Signed-off-by: Johan Euphrosine <proppy@google.com> (github: google)
Fix login prompt on push and pull because of error message
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Update lxc_template.go

If networking is disabled, but then pipework is used later to add nics, the network still doesn't function. Using flags=up for empty networking fixes this.
Docker-DCO-1.1-Signed-off-by: James DeFelice <james.defelice@ishisystems.com> (github: jdef)
Fix comparing binds and volume ids from other containers

Currently comparing volume ids for binds and other containers are broken
Fixes #3749
Fixes #3885
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Merge pull request #3911 from crosbymichael/fix-remove-volume

Fix comparing binds and volume ids from other containers
Merge pull request #3908 from crosbymichael/fix-login-prompt

Fix login prompt on push and pull because of error message
networkdriver: add ErrNoDefaultRoute

Docker-DCO-1.1-Signed-off-by: Johan Euphrosine <proppy@google.com> (github: google)
docker/config: update -mtu flag default

Docker-DCO-1.1-Signed-off-by: Johan Euphrosine <proppy@google.com> (github: google)
docs/cli: add mtu option

Docker-DCO-1.1-Signed-off-by: Johan Euphrosine <proppy@google.com> (github: google)
Updated width to 815 per comment.
Docker-DCO-1.1-Signed-off-by: Andy Rothfusz <github@developersupport.net> (github: metalivedev)
Vagrantfile port forwarding usages documented. Added usage via envvar FORWARD_PORTS for custom port or list of comma-separated ports
Docker-DCO-1.1-Signed-off-by: Keyvan Fatehi <keyvanfatehi@gmail.com> (github: keyvanfatehi)
Merge pull request #3883 from metalivedev/fix-3879

Fixes #3879 by updating embedding of ascii.io (now asciinema.io)
Do not call Put twice and do not call it on defer

Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Fix unmounts out of container export funcs
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Merge pull request #3188 from keyvanfatehi/vagrant-port-forwarding-list

Vagrantfile port forwarding made more flexible (w/ comments)
Merge pull request #3887 from proppy/detect-network-mtu

docker: detect defaultNetworkMtu from default route