Multi-go test
Genericizes the yaml+environment versioned configuration parser

Registry configuration parsing uses the new parser with a single version
declaration and an environment prefix of "REGISTRY"
Refactor token verification to support x5c header

Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Refactored out usage of strconv.Quote()

Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Fixes filesystem storage driver List semantics for nonexistent directory

Now returns a PathNotFoundError
Erm
Allows storagedriver parameter values to be of type interface{}

This enables use of nil, booleans, numeric types, and even complex structures for parameter values, assuming they can be parsed from yaml.
Merge pull request #858 from docker/CI

Multi-go test
Merge pull request #861 from BrianBland/ng-configuration

Genericizes the yaml+environment versioned configuration parser
Merge pull request #863 from BrianBland/ng-storagedriver

Fixes filesystem storage driver List semantics for nonexistent directory
Integrate auth.AccessController into registry app

This changeset integrates the AccessController into the main registry app. This
includes support for configuration and a test implementation, called "silly"
auth. Auth is only enabled if the configuration is present but takes measure to
ensure that configuration errors don't allow the appserver to start with open
access.
Merge pull request #865 from stevvooe/next-generation

Integrate auth.AccessController into registry app
Merge pull request #862 from jlhawn/ng_auth_package

Refactor token verification to support x5c header
Ensure that unset Context.Name only allowed on base route

If Context.Name is not set, the acceess controller may allow an unintended
request through. By only allowing a request to proceed without a name on the
base route, we provide some protection if future bugs forget to set the context
properly.
Merge pull request #867 from stevvooe/next-generation

Ensure that unset Context.Name only allowed on base route
Add pull by tag+digest support
Add mark/unmark
Pull by digest updates

Remove mark/unmark per IRC discussion
Always save all manifests; future extensions could manage caps.
Simplify code.