* Add Netherrack slabs and walls
Also adds deep netherrack stairs, and deep nether brick stairs, slabs, inner stairs and outer stairs.
Adds 9 new nodes in total.
* Treasure: Nether pickaxe takes 10x less wear damage when mining netherrack
cracky-3 mining time of Nether pickaxe reduced from 0.4 to 0.3 to mine netherrack faster.
maxlevel of nether pickaxe dropped from 3 to 2 to increase wear damage with non-netherrack nodes.
* Treasure: Nether staff of light
Adds "Nether staff of Light" and "Nether staff of Eternal Light"
One is limited to 60 uses, and the other has unlimited uses but the glowstone it creates will only last for 40 seconds.
There are no crafting recipes as I hope these to eventually be treasure that can be found in the nether.
See the pull request (#50) for more discussion
Adds a magma oceans region to the nether outside the existing nether caverns, which can be reached via tunnels.
Other misc changes:
* chatcomment nether_whereami, a debug aid for knowing which perlin-noise region you are in
* Nether ores no longer obtainable on the ceiling
* Move crafts into crafts.lua
* Add steam to lava cooling, and play bubbling lava upon death by lava
* Add cracked netherbrick
a decorative node which can only be obtained from dungeons or structures
I encourage someone to improve or replace the cracked netherbrick texture. For copyright purposes it's currently a derivative work (by me, 2020) from nether_brick.png, which is licensed under CC BY-SA 3.0 by PilzAdam, so it can fall under the "All other media" PilzAdam's credit in readme.md rather than need its own entry.
