remove 4 unused files
cleanup & fix (in parts) the CregLoadSaveHandler
fix LuaLoadSaveHandler in debug builds
fix & cleanup creg serializer
add creg loadsave test
creg: fix std::vector<bool> which is truely a BitArray instead of a vector (in bitarray each value takes 1bit, in vector it would be 1byte)
fix more creg classes
fix #3526 (falling trees cause segfault)
* don't rely on featureID in that code (until feature destruction is handled in it by id too. also falling trees will never got a valid featureID)
* I will create a 93.1 this weekend with this commit
save != safe