0.3.0: New item icons and elevator rando

Adds support for elevator randomization. When enabled, check icons appear on the elevator rooms. Elevators you can reach will show as green or yellow as usual, and elevators you can't access by walking through the door show as blue as long as you can use elevators (that is, you have Scan Visor or prescanned elevators). When you check off a blue elevator, it and all areas the elevator gives access to will be available in logic.

Also included in this update are new item icons for the visors, Missile Launcher, and Power Bomb Expansion.

There were also a few logic fixes, most notably progressive beams not being counted properly and the Map Station in Phen being mysteriously accessible.