Add cpu throttling stats.

Docker-DCO-1.1-Signed-off-by: Rohit Jnagal <jnagal@google.com> (github: rjnagal)
Merge pull request #5389 from tiborvass/5152-symlink-in-volume

Fixes #5152 : symlink in volume path
Another test to check for invalid stats.

Docker-DCO-1.1-Signed-off-by: Rohit Jnagal <jnagal@google.com> (github: rjnagal)
Merge pull request #5455 from rjnagal/cgroup-stats

Add throttling stats for cpu cgroup
Merge pull request #5443 from ncdc/commit-api-doc-fix

Docs fix: correct /commit info
Merge pull request #5441 from ostezer/docs-fix-notes-warnings-bg

Docs/CSS: Fix Notes/Warnings blocks' BG colour to improve its state.
Merge pull request #5439 from ostezer/docs-mkdocs-theme-maintainer-update

Docs/theme/MAINTAINERS: Modify/Update list of MAINTAINERS
Merge pull request #5414 from jamtur01/privreg

Addressed regression of private repository documentation.
add redirects from index/ -> docker-io/ and for the docker-io_api too

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@fosiki.com> (github: SvenDowideit)
Merge pull request #5438 from ostezer/docs-expand-viewport

Docs/CSS fix: Allow viewport expand to user's preference
remove the sphinx validation - we'll add a MarkDown one when we have it

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@fosiki.com> (github: SvenDowideit)
Update some whitespace in hack/make/test-integration-cli for consistency

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Remove obsolete 'bootcamp' project.

It was a nice idea to recruit more maintainers but we never found the
time to do it properly...

I am still interested in any ideas to make it easier to start
contributing!

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
Use "docker load" to create "scratch" in hack/make/test-integration-cli (instead of implicitly pulling it from the index)

Creating the "docker save" tarball for "scratch" is pretty simple.  I've also extrapolated the "docker build -t busybox ." logic into a separate "hack/make/.ensure-busybox" file so that it can eventually be reused easier.

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Merge pull request #5459 from shykes/remove-bootcamp

Remove obsolete 'bootcamp' project.
Merge pull request #5433 from SvenDowideit/remove-sphinx-validation-from-build

Remove Travis Sphinx validation
Update hack/dind to match the rest of our scripts

No functional changes here, just coding style and maintainability.

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Update hack/dind to mount cgroups on "/cgroup" instead of "/sys/fs/cgroup" for better compatibility

Fixes #5122

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
modernise the MAINTAINER process documentation to line up with what I understand it to be

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@fosiki.com> (github: SvenDowideit)
Use proper scheme with static registry
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)