Major performance improvements to the Dashboard and Calendar views

* Close the PHP session for writing as early as possible in most AJAX
  calls for those views
* Reduce the number of roundtrips to the server in both the Dashboard
  and Calendar views by putting the data in our HTML response (this
  makes a massive difference)
* Eliminated a couple of unneccessary AJAX calls
* Use lazy loading in full calendar
* Fixed a bug in the week view that only occurs near the end of the
  week (date->gmdate bug!)

airtime_mvc/application/controllers/LibraryController.php

@@ -403,6 +403,7 @@ class LibraryController extends Zend_Controller_Action
 
     public function contentsFeedAction()
     {
+        session_write_close();
         $params = $this->getRequest()->getParams();
 
         # terrible name for the method below. it does not only search files.