Adds `ObjectMeta.GenerateName`, an optional string field that defines
name generation behavior if a Name is not provided.

Adds `pkg/api/rest`, which defines the default Kubernetes API pattern
for creation (and will cover update as well). Will allow registries
and REST objects to be merged by moving logic on api out of those places.

Add `pkg/api/rest/resttest`, which will be the test suite that verifies
a RESTStorage object follows the Kubernetes API conventions and begin
reducing our duplicated tests.