Add kube-ui cluster addon for serving k8s dashboard UI.

Changes include:
- Add kube-ui binary for serving static dashboard UI
- Add kube-ui docker image, replication controller, and service
- Make the kube-ui a cluster-addon (enabled by default)
- Split the compiled pkg/ui/datafile.go into separate dashboard and swagger packages
- Update docs to reflect changes

pkg/ui/installsupport.go

@@ -20,6 +20,9 @@ import (
 	"mime"
 	"net/http"
 
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/ui/data/dashboard"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/ui/data/swagger"
+
 	assetfs "github.com/elazarl/go-bindata-assetfs"
 )
 
@@ -38,7 +41,11 @@ func InstallSupport(mux MuxInterface, enableSwaggerSupport bool) {
 	mime.AddExtensionType(".svg", "image/svg+xml")
 
 	// Expose files in www/ on <host>/static/
-	fileServer := http.FileServer(&assetfs.AssetFS{Asset: Asset, AssetDir: AssetDir, Prefix: "www"})
+	fileServer := http.FileServer(&assetfs.AssetFS{
+		Asset:    dashboard.Asset,
+		AssetDir: dashboard.AssetDir,
+		Prefix:   "www",
+	})
 	prefix := "/static/"
 	mux.Handle(prefix, http.StripPrefix(prefix, fileServer))
 	prefix = "/ui/"
@@ -48,7 +55,11 @@ func InstallSupport(mux MuxInterface, enableSwaggerSupport bool) {
 
 	if enableSwaggerSupport {
 		// Expose files in third_party/swagger-ui/ on <host>/swagger-ui
-		fileServer = http.FileServer(&assetfs.AssetFS{Asset: Asset, AssetDir: AssetDir, Prefix: "third_party/swagger-ui"})
+		fileServer = http.FileServer(&assetfs.AssetFS{
+			Asset:    swagger.Asset,
+			AssetDir: swagger.AssetDir,
+			Prefix:   "third_party/swagger-ui",
+		})
 		prefix = "/swagger-ui/"
 		mux.Handle(prefix, http.StripPrefix(prefix, fileServer))
 	}