Lighting reads blocktypes only for blocks under heightmap.

This should theoretically speed it up, since less data is copied back and forth.

Also implemented a possibly more cache-friendly blocklight starter algorithm (PrepareBlockLight2()), is disabled by default, needs perf testing.
Fixed member construction order.
Fixed link errors
Implemented Allocation Pool
Added callback for stopping starvation mode
Merge branch 'chunksparsing/structs' into AllocationPool
Use placement new to initalise objects
Implemented Allocation Pool use by cChunkData
Fixed bug in freeing NULL pointers
Merge branch 'chunksparsing/structs' into AllocationPool

Conflicts:
	src/ChunkData.cpp
	src/ChunkData.h
	tests/ChunkData/Coordinates.cpp
Fixed bad merge
merge master
Added logging
Fixed comments
Fill with buffer on startup
fixed const issue
fixed compile
fixed spaces
fixed spaces
reverted accedental android changes