Reintroduced .offset() as a default include, added original author credits.

src/offset.js

@@ -1,3 +1,6 @@
+// The Offset Method
+// Originally By Brandon Aaron, part of the Dimension Plugin
+// http://jquery.com/plugins/project/dimensions
 jQuery.fn.offset = function() {
 	var left = 0, top = 0, elem = this[0], results;