Entrance Rando... (kinda!)

With this update there is now support for an Entrance Rando*

some caveats:

• there is no logic related to the randomized map, things could be unreachable, darkrooms may be required, very likely you don't start with an available check, transitions that stop you in your tracks because they plop you into water
• like usual, no promises it has backwards compatibility
• there seems to be some bugs with the game not being sure which layer you should be on? please report if you find any of these

BUT, with ER off (a new yaml setting) nothing should be changed
with ER on, you will get a random map, and be able to traverse it (recommend cheating items in)
things to note about the ER decisions:

• doors/stairs that move you between layers (i.e. into houses, or into underground sections) are unchanged, i tried randoing these but they were too much headache so they're vanilla again
• the 'overworld' is not randomized, this is to enable things like baiting the sharks into allowing you to swim different locations, and to put the oasis, broken truck, thirsty man into reasonable locations
• some key regions are randomized together: the quicksand, the lighthouse, (really considering making dog house and the tile below it one as well..)
• land and water routes are split up meaning that some otherwise simple transitions become more complicated (i.e. south of dog house is three entrances, right of, left of, and the through the river) but if the water is split by land there is a water route and a land route (i.e. the bridge to lighthouse is one, and any water route west is a second one)