Add flag to enable cross domain requests in Api

Add the -api-enable-cors flag when running docker
in daemon mode to allow CORS requests to be made to
the Remote Api.  The default value is false for this
flag to not allow cross origin request to be made.

Also added a handler for OPTIONS requests the standard
for cross domain requests is to initially make an
OPTIONS request to the api.
Modified the navigation in both website and documentaion to include the Blog.
update doc to newer go
hack/ROADMAP.md: a high-level roadmap. Make a pull request to suggest changes
hack/PRINCIPLES.md: a list of principles guiding Docker's design. The goal is to scale the decision-making in the project and remove @shykes as a bottleneck as much as possible
Merge pull request #817 from dhrp/blog-in-navigation

Modified the navigation in both website and documentaion to include the blog.
Fixed some links

* Added Google group to FAQ on docs
* Changed IRC link
* Fixed link to contributing broken by 326faec
changed to 12.04 and add kernel
allow multiple params in inspect
add [] and move errors to stderr
Merge pull request #827 from dotcloud/dev_environment_update

Update "Setting Up a Dev Environment" doc, with modern golang  PPA and stable lxc kernel
Merge branch 'master' of ssh://github.com/dotcloud/docker
docker-build contrib script is deprecated by the new 'build' command
Daniel Mizyrycki is maintainer of dockerbuilder, the official build environment for docker binary releases
Update README.md
Typo in MAINTAINERS file
Merge branch 'master' of ssh://github.com/dotcloud/docker
Remove CR/NL from description in docker CLI. Also moved description shortening to the client
seperated the registry and index API's into their own docs

seperated the registry and index API's into their own docs and merged
in the index search api into the index api. Also renamed the original
registry api to registry_index_spec.
Build from Dockerfile on stdin requires a hypen
There is a missing hypen in the documentation:
    `docker build < Dockerfile` will complain
    `docker build - < Dockerfile` will not complain