Merge pull request #4778 from vbatts/vbatts-save_to_output

`docker save --output` flags
Merge pull request #4837 from crosbymichael/remove-ci

Remove docker-ci code from the repo
Merge pull request #4751 from enokd/master

Fixes #3369 Repeated slash-'/' characters; harmonize across all name-related commands
Merge pull request #4786 from SvenDowideit/run--lxc-conf-is-lxc-driver-only-atm

add a note that --lxc-conf is lxc-driver only.
Add Chef usage documentation

Docker-DCO-1.1-Signed-off-by: Brian Flad <bflad417@gmail.com> (github: bflad)
docker load: add --input flag

for those that do not care to read from redirected stdin

Docker-DCO-1.1-Signed-off-by: Vincent Batts <vbatts@redhat.com> (github: vbatts)
Fix typo in Using Chef documentation description

Docker-DCO-1.1-Signed-off-by: Brian Flad <bflad417@gmail.com> (github: bflad)
Merge pull request #4839 from bflad/chef-docker-docs

Add Chef usage documentation
docker load: doc clarification

Docker-DCO-1.1-Signed-off-by: Vincent Batts <vbatts@redhat.com> (github: vbatts)
Docker-DCO-1.1-Signed-off-by: Ryan Thomas <rthomas@atlassian.com> (github: rthomas)
Reminder for OSX users not to use SUDO

Useful for those who haven't made it to the examples page yet. https://github.com/chadoh/docker/commit/dad4a998dc716e506c874ce0e792989b9df28748

Docker-DCO-1.1-Signed-off-by: No Ducks <onemannoducks@gmail.com> (github: noducks)
check if working dir is a directory and raise corresponding errors when making dir.

Docker-DCO-1.1-Signed-off-by: Liang-Chi Hsieh <viirya@gmail.com> (github: viirya)
Merge pull request #4814 from noducks/master

Reminder for OSX users not to use SUDO
Force flag to prevent file already exists error.

Docker-DCO-1.1-Signed-off-by: No Ducks <onemannoducks@gmail.com> (github: noducks)
Merge pull request #4845 from noducks/link_fix

Force flag to prevent file already exists error.
docker load: added example of a multiple tag image

Docker-DCO-1.1-Signed-off-by: Vincent Batts <vbatts@redhat.com> (github: vbatts)
install.sh (get.docker.io) aufs comment updated.

devicemapper has landed, but the TODO hasn't been actioned presumably
because aufs is still preferred over devicemapper when available[1].

Comment updated accordingly.

Citation [1]: https://github.com/crosbymichael/docker/blob/267ca39921c35826ccbdb84fbbc0690bfef385d7/runtime/graphdriver/driver.go#L40-L46

Docker-DCO-1.1-Signed-off-by: Paul Annesley <paul@annesley.cc> (github: pda)
Merge pull request #4842 from pda/installer-devicemapper-comment

Update AUFS comment in install.sh
Merge pull request #4794 from alexlarsson/dm-better-shutdown

devicemapper: Better/faster shutdown
Merge pull request #4628 from kippandrew/port-allocator

Fix port collision with dynamically allocated ports