Disabled asserts in the release build (-DNDEBUG).

Added a safe variant of offset(const Slic3r::ExPolygon...), which offsets each loop separately.
New functions "remove_sticks" to remove zero area parts of polygons.
New functions "remove_small" and "remove_degenerate" for polygon clean up.
Extended the C++ supports, those are not finalized yet though.

xs/xsp/typemap.xspt

@@ -141,9 +141,9 @@
 %typemap{SupportLayer*};
 %typemap{Ref<SupportLayer>}{simple};
 
-%typemap{PrintSupportMaterial*};
-%typemap{Ref<PrintSupportMaterial>}{simple};
-%typemap{Clone<PrintSupportMaterial>}{simple};
+%typemap{PrintObjectSupportMaterial*};
+%typemap{Ref<PrintObjectSupportMaterial>}{simple};
+%typemap{Clone<PrintObjectSupportMaterial>}{simple};
 
 %typemap{PlaceholderParser*};
 %typemap{Ref<PlaceholderParser>}{simple};