New chat text is added as a copy of all previous chat and new one, use CList so it is not. Also adds a handy JS Interface addItem method to add new comments efficiently.
With this fix you can add a new message every onTick for 5000 ticks and not notice any performance hit (not like the current one that at 500 lines starts to drop fps).
Note that only List gets the additional JS function, even though COList inherits from it, because COList doesn't implement the clever addText setup.