Fix issue in ProgressBar when number of nodes/descs/arcs was less than 100.

src/main/org/insa/graphics/GraphReaderProgressBar.java

@@ -85,7 +85,7 @@ public class GraphReaderProgressBar extends JDialog implements GraphReaderObserv
 
     protected void initProgressBar(int index, int max) {
         progressBars[index].setMaximum(max);
-        modulos[index] = max / 100;
+        modulos[index] = Math.max(max / 100, 1);
     }
 
     protected void incCounter(int index) {