Added the delete option

scripts/keyboard.js

@@ -2,7 +2,6 @@ function Keyboard()
 {
   this.listen = function(event)
   { 
-    console.log(dotgrid);
     console.log(event.keyCode);
 
     switch (event.key || event.keyCode) {
@@ -10,7 +9,7 @@ function Keyboard()
       case 83 : dotgrid.draw_arc_c(); break;
       case 68 : dotgrid.draw_line(); break;
       case 70 : dotgrid.reset(); break;
-
+      case 71 : dotgrid.erase(); break;
     }
   }
 }