changed error message

src/main/java/org/gcube/portlets/user/workspace/server/GWTWorkspaceServiceImpl.java

@@ -1017,7 +1017,7 @@ public class GWTWorkspaceServiceImpl extends RemoteServiceServlet implements GWT
 						fakeFile.setName(itemName);
 						String itemRefMsg = trashedItem.isFolder()?"folder":"file";
 						itemRefMsg+=" '"+itemName+"'";
-						String errorMsg = "Error occurred on restoring the "+itemRefMsg;
+						String errorMsg = "Error occurred on restoring the "+itemRefMsg+". "+e.getMessage();
 						if(e instanceof UserNotAuthorizedException) {
 							errorMsg = String.format("Insufficent privileges for you to restore the %s in the selected folder", itemRefMsg);
 						}