Fix registry pushing/tagging

* docker push host:port/namespace/repo wouldn't push multiple tags for
  the same image
* getImageList was unnecessarily complex returning a nested array of
  ImgData when a correctly ordered list of images was sufficient
* removed various bits of redundancy

Docker-DCO-1.0-Signed-off-by: Danny Yates <danny@codeaholics.org> (github: codeaholics)
Remove unneeded DependencyGraph

Docker-DCO-1.0-Signed-off-by: Danny Yates <danny@codeaholics.org> (github: codeaholics)
Further simplification

Docker-DCO-1.0-Signed-off-by: Danny Yates <danny@codeaholics.org> (github: codeaholics)
Fix indentation to match rest of file (tabs, not spaces)

Docker-DCO-1.0-Signed-off-by: Danny Yates <danny@codeaholics.org> (github: codeaholics)
gofmt

Docker-DCO-1.0-Signed-off-by: Danny Yates <danny@codeaholics.org> (github: codeaholics)
Extract cgroups pkg.

Initial move before enhancing cgroups package.

Docker-DCO-1.1-Signed-off-by: Paul Nasrat <pnasrat@gmail.com> (github: pnasrat)
Merge branch 'fix-registry-push-tags' of https://github.com/codeaholics/docker into codeaholics-fix-registry-push-tags

Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Make sure new repositories can be pushed with multiple tags

Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Merge pull request #3681 from pnasrat/extract-cgroups-pkg

Extract cgroups into pkg sub dir
Don't expose cgroups via the execdriver API.

Use Resources to represent container limits rather than a cgroup specific field.

Docker-DCO-1.1-Signed-off-by: Paul Nasrat <pnasrat@gmail.com> (github: pnasrat)
Merge pull request #3684 from crosbymichael/push-multiple-tags

Push multiple tags for repository
Merge pull request #3685 from pnasrat/3679-cgroups-outside-lxc

Move Resources into exec driver
Fix support for registry auth with Dockerfile build.

Docker-DCO-1.1-Signed-off-by: Jake Moshenko <jake@devtable.com> (github: jakedt)
Merge pull request #3442 from DevTable/master

Fix support for registry auth with Dockerfile build.
Merge branch 'master' of https://github.com/dotcloud/docker