* Removes use of jquery.postmessage.js
* Fixes bug where Opera would attempt to use the hash transport and redirect to the dashboard.
* Fixes bug where multiple postMessage connections could not coexist in a single frame.
git-svn-id: http://svn.automattic.com/wordpress/trunk@20517 1a063a9b-81f0-0310-95a4-ce76da25c4cd