Stop all animations before performing scroll-to-bottom

So that if the animation is triggered multiple times you don't have to
wait for all the animations to be performed one after the other before
you can finally manually scroll.

static/application.js

@@ -402,7 +402,7 @@ function hideWaitAnimation() {
 
 function scrollToBottom() {
 	setTimeout(function () {
-		game_text.animate({scrollTop: game_text.prop('scrollHeight')}, 500);
+		game_text.stop(true).animate({scrollTop: game_text.prop('scrollHeight')}, 500);
 	}, 5);
 }