On error, exit from the loop, with error.
BAMResource::FrameForCycle() does not return a NULL bitmap on error,
but throws an exception. So, don't check for NULL in Actor::Draw(), but
put the Animation::Frame() call (which calls the former) into a try/catch
block.
Removed commented code
Made TLKEntry a refcounted object. TLKResource::EntryAt() now returns
a TLKEntry object instead of a pointer.