fire event on to once

Author: samid737

src/PathBuilder.js

@@ -5,7 +5,7 @@ var PathBuilder = function (scene) {
     this.systems = scene.sys;
 
     if (!scene.sys.settings.isBooted) {
-        scene.sys.events.on('boot', this.boot, this);
+        this.scene.sys.events.once('boot', this.boot, this);
     }
 };