Added data classes bases, Trivial modifications to many files

Update .gitignore, .htaccess, and 19 more files...

commons/content/data/metadata.php

@@ -0,0 +1,19 @@
+<?php
+// Making sure the file is included and not accessed directly.
+if(basename(__FILE__) == basename($_SERVER["SCRIPT_FILENAME"])) {
+	header('HTTP/1.1 403 Forbidden');
+	die();
+}
+
+// Including required helpers.
+include_once 'commons/langs.php';
+
+// Including subclasses.
+include_once 'commons/content/data/opengraph.php';
+include_once 'commons/content/data/twitter_card.php';
+
+class ContentMetadata {
+
+}
+
+?>