Add appengine/gcloud/mustache dependencies.

pkg/gcloud/lib/src/db/model_db.dart

+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+part of gcloud.db;
+
+/**
+ * A database of all registered models.
+ *
+ * Responsible for converting between dart model objects and datastore entities.
+ */
+abstract class ModelDB {
+  /**
+   * Converts a [datastore.Key] to a [Key].
+   */
+  Key fromDatastoreKey(datastore.Key datastoreKey);
+
+  /**
+   * Converts a [Key] to a [datastore.Key].
+   */
+  datastore.Key toDatastoreKey(Key dbKey);
+
+  /**
+   * Converts a [Model] instance to a [datastore.Entity].
+   */
+  datastore.Entity toDatastoreEntity(Model model) ;
+
+  /**
+   * Converts a [datastore.Entity] to a [Model] instance.
+   */
+  Model fromDatastoreEntity(datastore.Entity entity);
+
+  /**
+   * Returns the kind name for instances of [type].
+   */
+  String kindName(Type type);
+
+  /**
+   * Returns the property name used for [fieldName]
+   */
+  // TODO: Get rid of this eventually.
+  String fieldNameToPropertyName(String kind, String fieldName);
+}