add --all-tags to pull & pull latest by default

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
add a little documentation for docker pull

Docker-DCO-1.1-Signed-off-by: SvenDowideit <SvenDowideit@home.org.au> (github: SvenDowideit)
docker build: pull just latest if tag uspecified

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
pkg/tarsum: add dynamic buffer sizing

This commit makes tarsum buffer allocation dynamic. This change
is required to avoid allocating memory excessively after the archive
buffering changes.

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
Update docker_remote_api_v1.14.md

It is a tar stream, you should mention that somehow.

Here is the proof:

```
	host:~$ docker run -t -i ubuntu:14.04 bash
	root@c39be4c7b7c8:/# echo "my file contents" > abc
	root@c39be4c7b7c8:/# cat abc
	my file contents
	root@c39be4c7b7c8:/# exit
	host:~$ curl -H "Content-Type: application/json" -d '{"Resource":"/abc"}' http://localhost:4500/containers/c39be4c7b7c8/copy
	abc0100644000000000000000000000002112402102531007674 0ustar0000000000000000my file contents
	host:~$ curl -H "Content-Type: application/json" -d '{"Resource":"/abc"}' http://localhost:4500/containers/c39be4c7b7c8/copy > response_content
	  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
	                                 Dload  Upload   Total   Spent    Left  Speed
	100  2067  100  2048  100    19  56968    528 --:--:-- --:--:-- --:--:-- 58514
	host:~$ tar xvf response_content
	abc
	host:~$ cat abc
	my file contents
```

Docker-DCO-1.1-Signed-off-by: Mustafa Akın <mustafa91@gmail.com> (github: SvenDowideit)
Update export, copy and build API to sat 'TAR STREAM' for all versions.

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@docker.com> (github: SvenDowideit)
Very minor formatting update for docs/sources/articles/networking.md

Docker-DCO-1.1-Signed-off-by: James Turnbull <james@lovedthanlost.net> (github: jamtur01)
Added --device flag to run reference

Docker-DCO-1.1-Signed-off-by: James Turnbull <james@lovedthanlost.net> (github: jamtur01)
Merge pull request #7759 from unclejack/pull_latest_by_default

make docker pull only the latest tag by default
Merge pull request #7929 from SvenDowideit/doc-tar-stream

Sven Dowideit 	Update export, copy and build API to say 'TAR STREAM' for all versions.
Merge pull request #7930 from jamtur01/nformat

Very minor formatting update for docs/sources/articles/networking.md
Merge pull request #7931 from jamtur01/device

Added --device flag to run reference
add -p PORT as a valid format specification

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@docker.com> (github: SvenDowideit)
Make the side bar about in-document navigation by removing the duplicated h1

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@docker.com> (github: SvenDowideit)
Merge pull request #7949 from SvenDowideit/remove-doubled-up-page-heading

Make the side bar about in-document navigation by removing the duplicated h1
typo fix: immediatly -> immediately

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reformat the API docs so I can read them

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@docker.com> (github: SvenDowideit)
Change default label of container volumes to shared SELinux Label

Since these will be shared between containers we want to label
them as svirt_sandbox_file_t:s0.  That will allow multiple containers
to write to them.

Currently we are allowing container domains to read/write all content in
/var/lib/docker because of container volumes.  This is a big security hole
in our SELinux story.

This patch will allow us to tighten up the security of docker containers.

Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
Merge pull request #7951 from taohu/typo

typo fix: immediatly -> immediately
Merge pull request #7953 from SvenDowideit/reformat-api-docs

Reformat the API docs so I can read them