Add server/cache support to gaeconfig.

luci_config/appengine/format/default.go

Index: luci_config/appengine/format/default.go
diff --git a/luci_config/appengine/format/default.go b/luci_config/appengine/format/default.go
new file mode 100644
index 0000000000000000000000000000000000000000..a0b417185c56588cf6cd0a583ba67979f2cd42d5
--- /dev/null
+++ b/luci_config/appengine/format/default.go
@@ -0,0 +1,19 @@
+// Copyright 2016 The LUCI Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+// Package format implements a default FormatterRegistry configuration and
+// FormatterRegistry Context embedding.
+package format
+
+import (
+	"github.com/luci/luci-go/luci_config/server/cfgclient"
+	"github.com/luci/luci-go/luci_config/server/cfgclient/textproto"
+)
+
+// Default returns a new default FormatterRegistry configuration.
+func Default() *cfgclient.FormatterRegistry {
+	var fr cfgclient.FormatterRegistry
+	textproto.RegisterFormatter(&fr)
+	return &fr
+}