Make runtime less global for Codec

* Make Codec separate from Scheme
* Move EncodeOrDie off Scheme to take a Codec
* Make Copy work without a Codec
* Create a "latest" package that imports all versions and
  sets global defaults for "most recent encoding"
  * v1beta1 is the current "latest", v1beta2 exists
  * Kill DefaultCodec, replace it with "latest.Codec"
  * This updates the client and etcd to store the latest known version
* EmbeddedObject is per schema and per package now
* Move runtime.DefaultScheme to api.Scheme
* Split out WatchEvent since it's not an API object today, treat it
like a special object in api
* Kill DefaultResourceVersioner, instead place it on "latest" (as the
  package that understands all packages)
* Move objDiff to runtime.ObjectDiff

pkg/client/request_test.go

@@ -29,6 +29,7 @@ import (
 	"time"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api/latest"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
@@ -401,7 +402,13 @@ func TestWatch(t *testing.T) {
 
 		encoder := json.NewEncoder(w)
 		for _, item := range table {
-			encoder.Encode(&api.WatchEvent{item.t, runtime.EmbeddedObject{item.obj}})
+			data, err := api.NewJSONWatchEvent(latest.Codec, watch.Event{item.t, item.obj})
+			if err != nil {
+				panic(err)
+			}
+			if err := encoder.Encode(data); err != nil {
+				panic(err)
+			}
 			flusher.Flush()
 		}
 	}))