Added missing files

src/libslic3r/clipper.cpp

@@ -0,0 +1,13 @@
+// Hackish wrapper around the ClipperLib library to compile the Clipper library using Slic3r::Point.
+
+#include "clipper.hpp"
+
+// Don't include <clipper/clipper.hpp> for the second time.
+#define clipper_hpp
+
+// Override ClipperLib namespace to Slic3r::ClipperLib
+#define CLIPPERLIB_NAMESPACE_PREFIX	Slic3r
+// Override Slic3r::ClipperLib::IntPoint to Slic3r::Point
+#define CLIPPERLIB_INTPOINT_TYPE    Slic3r::Point
+
+#include <clipper/clipper.cpp>