[Fix] Preprocessor directives to compile Carve with clang
[Fix] Missing variable initialization (back ported from Fabian Gerold's commit in the IfcPlusPlus project).
[Fix] typo (back ported from Fabian Gerold's commit in the IfcPlusPlus project).
[Ref] Exposing a little more of the Mesh simplifier as public methods.
Merge branch 'clang'