add example

example/crawl.php

@@ -0,0 +1,19 @@
+#!/usr/bin/php
+<?php
+require_once(__DIR__.'/../vendor/autoload.php');
+
+if(!$url=$argv[1]??null){
+	die("url?\n");
+}
+
+use \JHodges\Sitemap\Crawler;
+
+$crawler=new Crawler();
+$crawler->crawl($argv[1]);
+
+foreach($crawler->getResults() as $url=>$result){
+        echo("{$result['code']} {$url}\n");
+        foreach($result['foundOn'] as $url=>$count){
+            echo("    -> ($count) $url\n");
+        }
+}