Sucessfully de-coupling of Big Key doors with dumb small key doors behind
Added a bit to trap door fixer so that we can hit the 3rd door in the door list
Added door list position info
Fixed graphics between HC/Sewers and cross dungeons.
Added base work for spiral staircases in HC/Eastern. (More data needed for other dungeons.)
Added new region to deal with push blocks in Sewers Secret Room
Refactored asm to be in multiple files.