Fixing unhandled exception when disposing player.

Hi I just fixed a bug which caused unhandled exception being thrown when destroy() method was called on a player. 

When iterating over ,,events'' array at jQuery.tubeplayer.js:800 there was no check if ,,_event'' relates to array element or it is a method of javascript array type. So after dealing with all the elements specified line above it crashed when ,,_event'' was equal to ,,remove'' (Array.remove method). See changes in my commit.

You might consider pulling this into main fork.