* moved spells to twig template

* removed useless spells.spell column that was duplicate of spells.words
* Usage_Statistics reports now plugin version too
* (internal) removed $hook_types array, using defined() and constant() functions now
* (internal) optimized Spells class

system/migrations/13.php

@@ -0,0 +1,4 @@
+<?php
+	if(fieldExist('spell', TABLE_PREFIX . 'spells'))
+		$db->query("ALTER TABLE `" . TABLE_PREFIX . "spells` DROP COLUMN `spell`;");
+?>