Use getTile() instead of imgDiv to get the correct element

The correct way to get the markup of a tile is to use getTile() - the
imgDiv will only be available if the tile does not use a frame.
.olTileReplacing is on the parent of .olTileImage when using frame
Make sure that drawTilesFromQueue gets executed

For events other than move, the tile queue may not be populated yet when
updateTimeout is called. So instead of checking for the queue's length,
we register the timer unconditionally in these cases.