Implemented the tick handler

examples/tickhandler.php

@@ -0,0 +1,23 @@
+<?php
+
+require_once __DIR__."/../vendor/autoload.php";
+
+/*
+ * This example demonstrate a possibility, but not a best practice. When using
+ * the tick handler, make sure the code being executed has ticks declared.
+ *
+ */
+
+use NoccyLabs\Gpio\Gpio;
+use NoccyLabs\Gpio\GpioTickHandler;
+
+$gpio = new Gpio(true);
+
+$gpiotick = new GpioTickHandler();
+$gpiotick->registerGpio($gpio);
+
+declare(ticks=5);
+
+while(true) {
+    usleep(10000);
+}