ADD:: added javadoc comments where needed for the checkstyle

EDIT:: edited some lines to fit the checkstyle

fixed some indentation warnings and line length warnings

src/Common/src/main/java/gogreen/common/UserDTO.java

@@ -1,12 +1,11 @@
 package gogreen.common;
 
 public class UserDTO {
-
-	private Long id;
+    private Long id;
     private String name;
 
     public UserDTO() {
-	}
+    }
 
     public UserDTO(Long id, String name) {
         this.id = id;