Fixes to build on openSUSE/Packman. (#67)

- Support different BINDIR, INCLUDEDIR and LIBDIR on install
- Take right python dir on x86_64 arch
- Fix build against Boost >= 1.58
- Make it possible to build libIfcGeom shared to reduce size of dependent binaries
- Fix INSTALL_RPATH
- Fix some more compiler warnings

src/ifcparse/IfcSpfHeader.h

@@ -34,7 +34,7 @@ private:
 	HeaderEntity& operator =(const HeaderEntity&); //N/A
 protected:
 	HeaderEntity(const char * const datatype, IfcSpfLexer* lexer) 
-		: _datatype(datatype), _list(0)
+		: _list(0), _datatype(datatype)
 	{
 		std::vector<unsigned int> ids;
 		_list = new ArgumentList();
@@ -193,4 +193,4 @@ public:
 
 }
 
-#endif
+#endif