[Feature Request] Topography mode

[9e7c2utr]

Topographic display for terrain and cave.

Terrain

Current terrain map is already great on its own so this probably not a big improvement.
Possible features and config.

• Blend (0.0 - 1.0)
  Blend terrain height with standard map, 0 = standard, 1 = full height mode
• Toggle height coloring [key]

Cave

ironbow scale

Current cave map is somewhat lacking, Map coloration which display stone, water, lava color barely helps with navigation and might work as well as black and white. This might require caching grayscale representation of altitude as well.

Possible features and config.

• Blend
• Toggle
• Upper relative altitude (n blocks above player)
• Lower relative altitude (n blocks below player)
• Different color scale