Added a basic stacktracing for assert and signal failures.
Fixed missing files in ProtoProxy.
Fixed QtBiomeVisualiser compilation.
Removed unneeded include.
Fixed MCADefrag compilation.
Merge pull request #1626 from mc-server/StackTraceOnFailure

Stack trace on failure
Improved comments for cWorld::DoWithPlayer().
Fixed compiling on linux.
Fixed nether ceiling
Fixed a crash in cSpawnPrepare.
Hopefully fixed random build fails