Changes for 1.6.0

properly detect ie9 in loader; refs #13186; !strict

fixes #4969 - went with dojo.cookie.useObject (get/setObject combinat…

…ion? - contemplated asObject, and others. change if

inappropriate) ... adds test to and enabled the cookie doh test. couldn't figure out a simple simple way to drop
useObject functionality into dojo.cookie without mini refactor.

Adding Date object support to dojo.clone(). Fixes #5284.

Added tests for dojo.clone().

Add final Greek strings. Thanks again, Dionysios. Fixes #5205

updating Safari version detection code to give us a real major versio…

…n number. Using that update to ensure that we get/set iframe properties correctly in dojo.io.iframe. Fixes #5012

make sure that exceptions and such don't fake IE out WRT base URL. Re…

…fs #4806

"." becomes "+", fixes #4449.

Replace removeChild with dojo._destroyElement. Refs #1927