registry: make certain headers optional

For a pull-only, static registry, there only a couple of headers that
need to be optional (that are presently required.
* X-Docker-Registry-Version
* X-Docker-Size
* X-Docker-Endpoints

Docker-DCO-1.1-Signed-off-by: Vincent Batts <vbatts@redhat.com> (github: vbatts)
registry: Info collection

roll version and standalone information into the _ping. And to support
Headers they are checked after the JSON is loaded (if there is anything
to load). To stay backwards compatible, if the _ping contents are not
able to unmarshal to RegistryInfo, do not stop, but continue with the
same behavior.

Docker-DCO-1.1-Signed-off-by: Vincent Batts <vbatts@redhat.com> (github: vbatts)
Engine: optional Logging field to disable custom logging in engine.

* The default behavior is preserved
* This disables the use of the `TEST` environment variable in engine.

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
Use apparmor_parser directly

The current load script does alot of things.  If it does not find the
parser loaded on the system it will just exit 0 and not load the
profile.  We think it should fail loudly if it cannot load the profile
and apparmor is enabled on the system.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Move apparmor to top level pkg
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Ignore is not exist error
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Generate imports based on what is avaliable
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Add missing "ps" requirement to PACKAGERS.md

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Replacing ASCII art image with real diagram

Docker-DCO-1.1-Signed-off-by: Aaron Huslage <huslage@gmail.com> (github: huslage)
This permission should be interpreted as octal, not decimal

Docker-DCO-1.1-Signed-off-by: Kato Kazuyoshi <kato.kazuyoshi@gmail.com> (github: kzys)
SQLite is also available in FreeBSD

Docker-DCO-1.1-Signed-off-by: Kato Kazuyoshi <kato.kazuyoshi@gmail.com> (github: kzys)
provide more information when TestTop tests fail

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
Add "validate" Makefile target

This was supposed to be part of my previous PR, but somehow got missed.

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Merge pull request #5248 from unclejack/more_info_testtop

provide more information when TestTop tests fail
Merge pull request #5230 from huslage/master

Replacing ASCII art image with real diagram
Fix for TOC "click/expand" & "scroll position" problem on mobile.

Fixes:

 - Click/expand
 - Scroll pos.
 - TOC table scroll-down arrow.
 - TOC title scrolls to top.

Docker-DCO-1.1-Signed-off-by: O.S. Tezer <ostezer@gmail.com> (github: ostezer)
Remove manually written TOCs from archived docs.

Docker-DCO-1.1-Signed-off-by: O.S. Tezer <ostezer@gmail.com> (github: ostezer)
Fix for broken in-document links which got scrambled during conversion.

Docker-DCO-1.1-Signed-off-by: O.S. Tezer <ostezer@gmail.com> (github: ostezer)
change inode map to struct from bool

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
Fix & improvements for mobile (& desktop) menu & submenu behaviour & issues.

Docker-DCO-1.1-Signed-off-by: O.S. Tezer <ostezer@gmail.com> (github: ostezer)