[FEATURE] Added ExceptionHandling functionality + tests.

- Somehow the ExceptionHandling functionality never really get implemented and/or got lost in translation, it's back whup!
- Added some basic tests for Middleware + routing.

test/Dummy/DummyController.php

@@ -0,0 +1,9 @@
+<?php
+
+class DummyController {
+
+    public function start() {
+        echo static::class . '@' .'start() OK';
+    }
+
+}