model notes are empty string by default

model/src/main/java/lcsb/mapviewer/model/map/model/ModelData.java

@@ -150,7 +150,7 @@ public class ModelData implements Serializable {
    * Description of the map.
    */
   @Column(columnDefinition = "TEXT")
-  private String notes;
+  private String notes = "";
 
   /**
    * Name of the map.