DATAES-23 : Add support for Nested Type (Root level initially)

src/main/java/org/springframework/data/elasticsearch/annotations/FieldType.java

@@ -1,7 +1,25 @@
+/*
+ * Copyright 2013 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 package org.springframework.data.elasticsearch.annotations;
 
 /**
+ * @author Rizwan Idrees
+ * @author Mohsin Husen
+ * @author Artur Konczak
  */
 public enum FieldType {
-    String, Integer, Long, Date, Float, Double, Boolean, Object, Auto
+    String, Integer, Long, Date, Float, Double, Boolean, Object, Auto, Nested
 }