Provide example of direct Slack linking for chatLinker

Author: themightychris

php-config/Laddr.config.d/chat.php

@@ -2,12 +2,6 @@
 
 /*
 Laddr::$chatLinker = function($channel = null) {
-    $url = '/chat';
-
-    if ($channel) {
-        $url .= '?channel=' . urlencode($channel);
-    }
-
-    return $url;
+    return 'https://mySlackOrg.slack.com/messages/'.urlencode($channel ?: 'general').'/';
 };
 */