Improve default parameters
Update and improve documentation
Unhide mapgen, but is still unstable

Remove CaveFractal
Add a lava depth constant to CaveV5 to make it universal

Complete set of parameters for each of mandelbrot and julia sets
The julia set structure often needs different iterations and scale

Player now spawns on julia set due to julia offset
Add commented-out '#include profiler.h' for timetaker use
Use v3fs to reduce number of parameters
Tune tunnel width to match mgv7

Decorations: Remove lower limit of water level for placement

Mgv5/v7: Fix generateBiomes biome recalculation logic Biomegen down to y = -192 for mgv5 deep oceans. Improve code

Mgv5: Add large_cave_depth constant

Add large pseudorandom caves below -256
De-link terrain level from water_level
Cavegen: Mgv5 large cave code

Caves check for biome nodes, only excavate stone under water level
Unease caves noises, use MT0.3 parameters
Blobgen after cavegen
Biomegen: remove 'is replaceable content' bool

This fixes biome surface in tunnels

Use/add stone_surface_max_y to speed-optimise/guide dungeon generation
MgV7: Don't let mountain terrain chop dungeons at mapchunk borders
Make mountain terrain update stone_surface_max_y for caves in mountains

Add support for notify-on-decoration
Clean up mapgen constructors
Clean up mapgen.cpp code style somewhat
Remove trailing whitespace from some files

Add BiomeManager, OreManager, DecorationManager, and SchematicManager

MapgenParams is no longer a polymorphic class, eliminating the need for messy and bug-prone reallocations.
Separation between the common and mapgen-specific parameters is now strongly defined.
Mapgen parameters objects are now properly encapsulated within the proper subsystems.