Merging changes to Set class into 1.1.x.x

Added doc comment for Set::reverse()
merged changes in DboSource and DboPostgres into 1.1.x.x

git-svn-id: https://svn.cakephp.org/repo/branches/1.2.x.x@5420 3807eeeb-6ff5-0310-8944-8be069107fe0

cake/libs/set.php

@@ -662,7 +662,12 @@ class Set extends Object {
 
 		return array_combine($keys, $vals);
 	}
-
+/**
+ * Converts an object into an array
+ *
+ * @param object $object
+ * @return array
+ */
 	function reverse($object) {
 		if (is_object($object)) {
 			$merge = array();