Ported Polygon->is_counter_clockwise() and rearranged code in .cpp files

xs/xsp/Polygon.xsp

@@ -21,6 +21,7 @@
         %code{% const char* CLASS = "Slic3r::Polyline"; RETVAL = THIS->split_at_index(index); %};
     Polyline* split_at_first_point()
         %code{% const char* CLASS = "Slic3r::Polyline"; RETVAL = THIS->split_at_first_point(); %};
+    bool is_counter_clockwise();
 %{
 
 Polygon*

xs/xsp/typemap.xspt

@@ -1,3 +1,4 @@
+%typemap{bool}{simple};
 %typemap{std::string};
 %typemap{std::vector<unsigned int>*};
 %typemap{SV*};