merge existing config when committing

Fixes #1141

Docker-DCO-1.1-Signed-off-by: Wes Morgan <cap10morgan@gmail.com> (github: cap10morgan)
Show some ENV / local updated baseimage tricks that use an apt-cacher-ng proxy to make debian based installations instant

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@fosiki.com> (github: SvenDowideit)
implement pharvey's suggestions

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@home.org.au> (github: SvenDowideit)
devmapper: Add per-device lock

We currently use a global lock to protect global data (like the
Devices map) as well as device data itself and access to
(non-threadsafe) libdevmapper.

This commit also adds a per-device lock, which will allow per-device
operations to temporarily release the global lock while e.g. waiting.
The per-device lock will make sure that nothing else accesses that
device while we're operating on it.

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
devmapper: Increase sleep times and unlock while sleeping

We've seen some cases in the wild where waiting for unmount/deactivate
of devmapper devices taking a long time (several seconds). So, we increase
the sleeps to 10 seconds before we timeout. For instance:

https://github.com/dotcloud/docker/issues/4389

But, in order to not keep other processes blocked we unlock the global
dm lock while waiting to allow other devices to continue working.

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
Note within the RELEASE-CHECKLIST that "origin" is assumed to be upstream

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Adding the new options to the `docker ps` documentation.

URL of documentation page is: http://docs.docker.io/en/latest/reference/commandline/cli/#ps

Docker-DCO-1.1-Signed-off-by: Scott Collier <emailscottcollier@gmail.com> (github: scollier)
Adding options to `docker restart` documentation

URL of page is: http://docs.docker.io/en/latest/reference/commandline/cli/#restart

Docker-DCO-1.1-Signed-off-by: Scott Collier <emailscottcollier@gmail.com> (github: scollier)
All caps variables in normal bash should be avoided not to accidentally collide with environment variables.

Docker-DCO-1.1-Signed-off-by: Rovanion Luckey <rovanion.luckey@gmail.com> (github: Rovanion)
Fix init script cgroup mounting workarounds to be more similar to cgroupfs-mount and thus work properly

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Add variable for DOCKER_LOGFILE to sysvinit and use append instead of overwrite in opening the logfile

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Remove goroutine leak upon error

Docker-DCO-1.1-Signed-off-by: Guillaume J. Charmes <guillaume@charmes.net> (github: creack)
Update parseLxcInfo to comply with new lxc1.0 format

Docker-DCO-1.1-Signed-off-by: Guillaume J. Charmes <guillaume@charmes.net> (github: creack)
Merge pull request #4504 from alexlarsson/devicemapper-waits

devmapper: Increase sleep times and unlock while sleeping
Merge pull request #4521 from tianon/release-checklist-origin

Note within the RELEASE-CHECKLIST that "origin" is assumed to be upstream
Merge pull request #4598 from creack/fix_lxc

Fix lxc
Fix attach exit on darwin

Docker-DCO-1.1-Signed-off-by: Guillaume J. Charmes <guillaume@charmes.net> (github: creack)
Adding the new options to the `docker ps` documentation.

URL of documentation page is: http://docs.docker.io/en/latest/reference/commandline/cli/#ps

Docker-DCO-1.1-Signed-off-by: Scott Collier <emailscottcollier@gmail.com> (github: scollier)

Adding the new options to the `docker ps` documentation.

URL of documentation page is: http://docs.docker.io/en/latest/reference/commandline/cli/#ps

Docker-DCO-1.1-Signed-off-by: Scott Collier <emailscottcollier@gmail.com> (github: scollier)

Adding CLI options to the commandline reference documentation.

URLs of pages are:
http://docs.docker.io/en/latest/reference/commandline/cli/

Docker-DCO-1.1-Signed-off-by: Scott Collier <emailscottcollier@gmail.com> (github: scollier)

changing indention

Docker-DCO-1.1-Signed-off-by: Scott Collier <emailscottcollier@gmail.com> (github: scollier)
improve deprecation message

Docker-DCO-1.1-Signed-off-by: Victor Vieux <victor.vieux@docker.com> (github: vieux)
Adding CLI options to the commandline reference documentation.

Fixing bad DCO sig

URLs of pages are:
http://docs.docker.io/en/latest/reference/commandline/cli/

Docker-DCO-1.1-Signed-off-by: Scott Collier <emailscottcollier@gmail.com> (github: scollier)