impliment of the method in symbol.cpp and correct the former errors.
merge the files together.
Merge branch 'master' of https://github.com/labproject/ProceduralBuidings

Conflicts:
	ProdeduralBuildingGenerator/Integration.h
	ProdeduralBuildingGenerator/Modeling.cpp
Merge branch 'master' of https://github.com/labproject/ProceduralBuidings