mount of /.dockerinit is not needed for native driver, so move it into lxc driver

Docker-DCO-1.1-Signed-off-by: Albert Zhang <zhgwenming@gmail.com> (github: zhgwenming)
Add support for client certificates for registries

This lets you specify custom client TLS certificates and CA root for a
specific registry hostname. Docker will then verify the registry
against the CA and present the client cert when talking to that
registry.  This allows the registry to verify that the client has a
proper key, indicating that the client is allowed to access the
images.

A custom cert is configured by creating a directory in
/etc/docker/certs.d with the same name as the registry hostname. Inside
this directory all *.crt files are added as CA Roots (if none exists,
the system default is used) and pair of files <filename>.key and
<filename>.cert indicate a custom certificate to present to the registry.

If there are multiple certificates each one will be tried in
alphabetical order, proceeding to the next if we get a 403 of 5xx
response.

So, an example setup would be:
/etc/docker/certs.d/
└── localhost
    ├── client.cert
    ├── client.key
    └── localhost.crt

A simple way to test this setup is to use an apache server to host a
registry. Just copy a registry tree into the apache root, here is an
example one containing the busybox image:
  http://people.gnome.org/~alexl/v1.tar.gz

Then add this conf file as /etc/httpd/conf.d/registry.conf:

 # This must be in the root context, otherwise it causes a re-negotiation
 # which is not supported by the tls implementation in go
 SSLVerifyClient optional_no_ca

 <Location /v1>
 Action cert-protected /cgi-bin/cert.cgi
 SetHandler cert-protected

 Header set x-docker-registry-version "0.6.2"
 SetEnvIf Host (.*) custom_host=$1
 Header set X-Docker-Endpoints "%{custom_host}e"
 </Location>

And this as /var/www/cgi-bin/cert.cgi

 #!/bin/bash
 if [ "$HTTPS" != "on" ]; then
     echo "Status: 403 Not using SSL"
     echo "x-docker-registry-version: 0.6.2"
     echo
     exit 0
 fi
 if [ "$SSL_CLIENT_VERIFY" == "NONE" ]; then
     echo "Status: 403 Client certificate invalid"
     echo "x-docker-registry-version: 0.6.2"
     echo
     exit 0
 fi
 echo "Content-length: $(stat --printf='%s' $PATH_TRANSLATED)"
 echo "x-docker-registry-version: 0.6.2"
 echo "X-Docker-Endpoints: $SERVER_NAME"
 echo "X-Docker-Size: 0"
 echo

 cat $PATH_TRANSLATED

This will return 403 for all accessed to /v1 unless *any* client cert
is presented. Obviously a real implementation would verify more details
about the certificate.

Example client certs can be generated with:

openssl genrsa -out client.key 1024
openssl req -new -x509 -text -key client.key -out client.cert

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
Revert "removed expect from mkimage-arch since it was not working"

This reverts commit 962e1186f9a0a43344e19dcf70bac159f0eafb4e.

Conflicts:
	contrib/mkimage-arch.sh

Docker-DCO-1.1-Signed-off-by: Zoltan Tombol <zoltan.tombol@gmail.com> (github: ztombol)
Fix expect script in mkimage-arch

Docker-DCO-1.1-Signed-off-by: Zoltan Tombol <zoltan.tombol@gmail.com> (github: ztombol)
Skipping empty lines in .dockerignore

Docker-DCO-1.1-Signed-off-by: Ian Babrou <ibobrik@gmail.com> (github: bobrik)
Set state running before dumping to disk

Fixes #4766
Docker-DCO-1.1-Signed-off-by: Alexandr Morozov <lk4d4math@gmail.com> (github: LK4D4)
add systemd MAINTAINERS file

	new file:   contrib/init/systemd/MAINTAINERS

Docker-DCO-1.1-Signed-off-by: Lokesh Mandvekar <lsm5@fedoraproject.org> (github: lsm5)
use systemd socket-activation by default

	modified:   contrib/init/systemd/docker.service
	renamed:    contrib/init/systemd/socket-activation/docker.socket -> contrib/init/systemd/docker.socket
	deleted:    contrib/init/systemd/socket-activation/docker.service

Docker-DCO-1.1-Signed-off-by: Lokesh Mandvekar <lsm5@fedoraproject.org> (github: lsm5)
systemd unitfile requires docker.socket

	modified:   contrib/init/systemd/docker.service

Docker-DCO-1.1-Signed-off-by: Lokesh Mandvekar <lsm5@fedoraproject.org> (github: lsm5)
The installer completed page now contains information on next steps, so is more useful than the intro

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@docker.com> (github: SvenDowideit)
since moved the ./dockerinit mount into lxc driver, fix the lxc testcase accordingly

Docker-DCO-1.1-Signed-off-by: Albert Zhang <zhgwenming@gmail.com> (github: zhgwenming)
no need to create a link to the docker binary
Merge pull request #7029 from albers/patch-2

no need to create a link to the docker binary
Add small note about AUFS layer limitation
Docker-DCO-1.1-Signed-off-by: Michaël Pailloncy <mpapo.dev@gmail.com> (github: mpapo)
Update small note about layer limitation
Docker-DCO-1.1-Signed-off-by: Michaël Pailloncy <mpapo.dev@gmail.com> (github: mpapo)
Adjust Link description to match target

The target document headline is "Managing data in containers" and so should the link be named.
Removed legacy api.md file

Docker-DCO-1.1-Signed-off-by: James Turnbull <james@lovedthanlost.net> (github: jamtur01)
Merge pull request #6855 from SvenDowideit/update-osx-installer-image-to-show-final-page

The installer completed page now contains information on next steps, so ...
Merge pull request #7037 from henning/patch-3

Adjust Link description to match target
Merge pull request #6892 from mpapo/docs-docker-aufs-limitation

Add small note about AUFS layer limitation