Move NumericalConstant to basics

Some classes in basics also use numerical constants (currently from UbMath.h). We want to get rid of the constants in UBMath.h in (#58 (closed)), but there is a problem: NumericalConstant.h is located in lbm and lbm links against basics. Therefore linking basics against lbm would create a circular dependency. That is why we need to move NumericalConstant to basics.