Fixed issue with the calendar entering recursive loops
Changed event calendar to an internal class

 - This aligned it with the other classes contained in this plugin. Also
   changed the internal reference variable to match.
Refactored dateSlider function

 - This is a fairly large function, I hopefully made it a little easier
   to follow. Also first attempt to separate logic from DOM manipulation
Refactored out some of the calendar initialisation

 - Not yet complete - this really breaks the calender functionality.
   Committing now to share.
Inlined sort function