Fixed Javadoc in GroupResizeEvent

src/main/java/envoy/event/GroupResizeEvent.java

@@ -5,6 +5,10 @@ import envoy.data.Group;
 import envoy.data.User;
 
 /**
+ * This event is used to communicate changes in the group size between client
+ * and server.<br>
+ * Possible actions are adding or removing certain {@link User}s to or from a certain {@link Group} 
+ * <br>
  * Project: <strong>envoy-common</strong><br>
  * File: <strong>GroupResizeEvent.java</strong><br>
  * Created: <strong>25 Mar 2020</strong><br>
@@ -20,6 +24,10 @@ public class GroupResizeEvent extends Event<Long> {
 	private static final long serialVersionUID = 0L;
 
 	/**
+	 * This enum defines all possibilities for handling
+	 * {@link GroupResizeEvent}s.<br>
+	 * These can be: {@link OperationType#ADD} or {@link OperationType#REMOVE}.<br>
+	 * <br>
 	 * Project: <strong>envoy-common</strong><br>
 	 * File: <strong>GroupResizeEvent.java</strong><br>
 	 * Created: <strong>25 Mar 2020</strong><br>
@@ -29,11 +37,13 @@ public class GroupResizeEvent extends Event<Long> {
 	 */
 	public enum OperationType {
 		/**
-		 *
+		 * Select this element, if the given {@link User} should be added to the given
+		 * {@link Group}
 		 */
 		ADD,
 		/**
-		 *
+		 * Select this element, if the given {@link User} should be removed from the
+		 * given {@link Group}
 		 */
 		REMOVE
 	}