I've patched the problem so that ActionLayer checks for a valid ID before doing anything, and does a no-op for IDs it doesn't know how to handle. However, this only fixes the problem during gameplay. It's quite possible that hitting the triangle button in other places in the app might equally cause a crash.
Issue: 544
Added basic transition system that works with GameApp's phases. Currently does a fade-out between elements, which works well in some places and not-so-well in others. We'll definitely want to think about where and where not to use it... they'd work a lot better if we could spawn a thread to handle loading the next state while transitioning.
Also cleaned up the shop a bit, so it uses ReadButton() instead of GetButtonClick()-- hence the slight change to JGE. Added a tiled image for the task board, which loads conservatively (I tried 128x128, but it didn't look as good).
