title: add item direction in tileList component
body: <p>I have Flash AS3 Project with tile list.
  I have buttons on stage. each of them when clicked adds tile with a picture on it to the tileList using the addTile() function.
  I'm using 2 columns in the tile list and I want the new tiles will appear from right to left (1st item - right column, 2nd item - left column..).
  is it possible?
  additionally, is it possible that each new item will be added to the top of the tileList instead of the bottom of it?</p>
  
  <p>thank!</p>