Updated our code to stop Fabric of Reality platforms from generating
under exits all the time. Now they generate only when the supporting
blocks are replaceable (in which case they're replaced by FoR) or when
they're not opaque solids or have tile entities (then FoR generates on
top). The exit search algorithm treats replaceable non-liquid blocks as
air, so an attempt is made to build against the ground and not on top of
replaceable blocks. The area around the door is cleared of blocks to
avoid killing the player with lingering replaceable blocks that might be
harmful, like poison ivy.
Fixed a bug in BaseGateway that would cause it to still crash servers
during world generation. The import filters must be applied before
searching for doors because GatewayBlockFilter uses Forge-provided block
IDs and not the standard export values. Also fixed a comment in
yCoordHelper that cut off strangely.
1. Made World Thread available as dungeon loot
2. Removed useless config options for loot that doesn't appear anymore
3. Tweaked some config names and variable names for consistency
