Adding first draft of Official Repo Guidelines

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
Revisions based on feedback.

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
Format and typo fixes

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
More format fixes.

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
More format wrestling.

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
Fix formatting, change to markdown block for long

Signed-off-by: Joe Ferguson <joe@infosiftr.com>
Merge pull request #1 from yosifkit/adding_official-repo-guidelines

Fix formatting, change to markdown block for long
Fixes a couple small typos

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
Merge branch 'adding_official-repo-guidelines' of https://github.com/fredlf/docker into adding_official-repo-guidelines

Conflicts:
	docs/sources/docker-hub/official_repos.md

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
Fix for user kicked off after login on some hosts

Docker-DCO-1.1-Signed-off-by: SvenDowideit <SvenDowideit@home.org.au> (github: SvenDowideit)
Change content-type for json stream to application/x-json-stream.

Docker-DCO-1.1-Signed-off-by: Jessica Frazelle <jess@docker.com> (github: jfrazelle)
Persistent directory for container in execdriver

This is needed for persistent namespaces

Signed-off-by: Alexandr Morozov <lk4d4math@gmail.com>
Test on execdriver dir behavior

Signed-off-by: Alexandr Morozov <lk4d4math@gmail.com>
That URL isn't there anymore

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@docker.com> (github: SvenDowideit)
Merge pull request #8101 from jfrazelle/6974-correct-ct-json-stream

Change content-type for json stream to application/x-json-stream.
builder: properly communicate onbuild trigger information during
subsequent builds.

Docker-DCO-1.1-Signed-off-by: Erik Hollensbe <github@hollensbe.org> (github: erikh)
Make sure COPY/ADD on dirs doesn't grab too many files
Add check for / first - per LK4D4's comment.
Add a comment to explain why we're adding a /

Signed-off-by: Doug Davis <dug@us.ibm.com>
Adding new Dockerfile Best Practices doc, and links thereto.

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
Merge pull request #8187 from erikh/builder_onbuild_output

builder: properly communicate onbuild trigger information during subsequent builds.
Merge pull request #8186 from duglin/ErrInCopyCache

Make sure COPY/ADD on dirs doesn't grab too many files