Merge master
Fix merge issue
Make docker build flush output each line
Small fix
Merge pull request #733 from meejah/master

Documentation: Use add-apt-repository instead of editing sources.list
Removed deprecated SPECS directory
Merge pull request #702 from kim0/patch-2

Properly install ppa, avoid GPG key warning. Also closes #715
De-duplicated contribution instructions. The authoritative instructions are in CONTRIBUTING.md at the root of the repo.
Merge branch 'master' of ssh://github.com/dotcloud/docker
Send error without headers when using chunks
Add directory contents instead of while directory for docker build
Fill the multipart writer directly instead of using reader
Readd build tests
Make sure the last line of docker build is the image id
Merge pull request #732 from dotcloud/718-return_no_such_container_as_404-fix

- API: return 404 on no such containers in /attach
Merge pull request #731 from dotcloud/change_containersPs_containersJson_api-feature

* API: rename containers/ps to containers/json
Merge pull request #730 from dotcloud/invert_status_created-fix

- Runtime: invert status created in docker ps
Cereate a new registry object for each request (~session)
Update tests with new cookies for registry
Documented who decides what and how.