print thousand delimiter (of whatever they are called)

pdb-plotting/src/main/java/org/lucares/recommind/logs/Plotter.java

@@ -218,7 +218,7 @@ public class Plotter {
 		}
 
 		result.append(" (");
-		result.append(values);
+		result.append(String.format("%,d", values));
 		result.append(")");
 
 		return result.toString();