Make directional fog colors respect tonemap
Disable loading .mtl files. Theyre not used anyway.
Add flags and lacunarity as new noise parameters

Add 'absolute value' option to noise map functions
Extend persistence modulation to 3D noise
Extend 'eased' option to noise2d_perlin* functions
Some noise.cpp formatting fixups
Always escape user provided data in mainmenu fields
Fix lighting artifacts (Issue #1887).
Fix struct vs. class in forward declarations
Optimize noise implementations
Merge remote-tracking branch 'minetest/master' into stable

Conflicts:
	src/client.cpp
	src/mapgen_v5.cpp
	src/mapgen_v7.cpp
	src/mg_biome.cpp
	src/noise.cpp
	src/noise.h
convert fm noiseparams