Changed all db constructors to newer syntax, made insert_id() function more convenient for postgres on pdo driver
diff --git a/system/database/DB_forge.php b/system/database/DB_forge.php
index 0dd29c2..6bc4041 100644
--- a/system/database/DB_forge.php
+++ b/system/database/DB_forge.php
@@ -35,7 +35,7 @@
 	 * Grabs the CI super object instance so we can access it.
 	 *
 	 */
-	function CI_DB_forge()
+	function __construct()
 	{
 		// Assign the main database object to $this->db
 		$CI =& get_instance();