Fix issue with observers.

src/main/org/insa/graphics/drawing/components/MapZoomControls.java

@@ -1,5 +1,6 @@
 package org.insa.graphics.drawing.components;
 
+import java.awt.BasicStroke;
 import java.awt.Color;
 import java.awt.Component;
 import java.awt.Cursor;
@@ -173,6 +174,8 @@ public class MapZoomControls {
         g.drawImage(zoomOut, xoffset, yoffset, observer);
         zoomOutRect.setBounds(xoffset, yoffset, DEFAULT_HEIGHT, DEFAULT_HEIGHT);
 
+        g.setStroke(new BasicStroke(1));
+
         // Draw ticks
         xoffset += DEFAULT_HEIGHT + 2;
         g.setColor(ZOOM_TICK_COLOR);