Add Option to not store the id property in the document source.

Closes spring-projects#2364

Author: sothawo

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

@@ -77,6 +77,14 @@
 	 */
 	Dynamic dynamic() default Dynamic.INHERIT;
 
+	/**
+	 * Specifies if the id property should also be stored in the Elasticsearch document source. Default value is
+	 * {@literal true}
+	 *
+	 * @since 5.1
+	 */
+	boolean storeIdInSource() default true;
+
 	/**
 	 * @since 4.3
 	 */