Sort of implementation of chunk sparsing

Issues:
* Chunks are flipped
* Slow/inefficient/badly coded
* Only blocktypes are 'compressed'
Performance improvements and chunk flipping fixed
Fixed some bugs

* Fixed undefined behaviour
* Fixed compression failure
Merge remote-tracking branch 'origin/master' into chunkysparsing
Speed and memory improvements

* Changed array to be continuous, so no more layer splitting
Nibbletypes are compressed

+ Added nibble compression
* Fixed an off by one
Blocklight and skylight now compressed
Attempt to fix errors
Statistic/Achievement defs
Maybe speed improvements?

* Use a single index to determine from when to begin copying data
* Use heightmap to determine first nonair block
Replaced all the .data() calls so the code compiles in VS2008
Mobs shouldn't burn when it's Raining #906
Updated NetherFort prefabs from the Gallery server.
Fireproof status getter and setter.
Added IsFireproof hook for monsters.ini
Declaration that a mob is not fireproof is implicit.

Removed explicitly declaring mobs as not fireproof.
Renamed getter and setter for IsFireproof.
Merge pull request #925 from archshift/master

Added monsters.ini rule for fireproof mobs.
Mobs shouldn't burn when it's Raining #906
Mob Knockback is far too much #776
Merge branch 'master' of https://github.com/mc-server/MCServer