Updated map and mapgroup macros to get around an rgbds bug.
Legendary beast locale handling annotated and relabeled.
Added a new constant NUM_ENGINE_FLAGS for use in the EngineFlagAction function. This will make it easier for modders to add or remove engine flags.
Updated macros that rely on the GROUP_, MAP_ constants to use the map macro
Added GROUP_NONE and MAP_NONE for the sake of compatibility with this new scheme
Added new macro elevfloor to simplify the definition of elevators under this new scheme
Replaced encounter rates with percent values
Added new constants denoting the number of wild Pokemon in the grass and water wild constructs
Annotated and relabeled the encounter generating functions
Renamed a WRAM address associaed with the temporary storage of the wild Pokemon's species
Moved spawn constants to constants/map_constants.asm for use anywhere in the disassembly
Annotated the SGB functions in predef/sgb.asm, and some of the map scripts. Renamed several functions in home. Renamed six WRAM addresses corresponding to party icon animations, and renamed several others relative to these.
