Implemented trapped chests & others

+ Added trapped chests
* Fixed a bunch of bugs in the redstone simulator concerning wires and
repeaters
* Other potential bugfixes

I hereby present to xoft, ONE METRIC TON PRECISELY -----------------
-------------------------------  of code to review.

With thanks.
So if a_OtherChunk is passed, it is the chunk that had a block change, and a_Chunk is the neighbouring chunk of that block. Because said neighbouring chunk does not know of this change but still needs to update its redstone, we set it to dirty.

I should probably paste this comment in.