Stop router from processing routes if no valid route is found.

src/Pecee/SimpleRouter/SimpleRouter.php

@@ -48,6 +48,11 @@ class SimpleRouter
      */
     public static function start()
     {
+        // Stop processing routes if no valid route is found.
+        if(static::request()->getUrl()->getPath() === null) {
+            return;
+        }
+
         echo static::router()->routeRequest();
     }