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/public/js/airtime/schedule/full-calendar-functions.js

@@ -362,11 +362,14 @@ function windowResize() {
 function preloadEventFeed () {
     var url = baseUrl+'Schedule/event-feed-preload';
     var d = new Date();
+    createFullCalendar({calendarInit: calendarPref});
 
+/*
     $.post(url, {format: "json", cachep: d.getTime()}, function(json){
         calendarEvents = json.events;
         createFullCalendar({calendarInit: calendarPref});
     });
+   */
 }
 
 var initialLoad = true;