- add Policy API to pkg/scheduler/apis/config and staging/src/k8s.io/kube-scheduler/config/v1
- dual-register Policy as apiGroup "v1" and "kubescheduler.config.k8s.io
- move/merge pkg/scheduler/api to pkg/scheduler/apis/config/...
- alias schedulerapi to pkg/scheduler/apis/config
- alias legacyapi to pkg/scheduler/api
- eliminate latest.Codec; use scheme.Codecs instead
- unit tests to verify Policy YAML with version "v1" or "kubescheduler.config.k8s.io/v1" can be loaded properly
- update api/api-rules/violation_exceptions.list
