added end_program() function to GCodeWriter

xs/src/libslic3r/GCodeWriter.cpp

@@ -511,6 +511,15 @@ GCodeWriter::get_position() const
     return this->_pos;
 }
 
+std::string
+GCodeWriter::end_program()
+{
+    std::ostringstream gcode;
+    if (FLAVOR_IS(gcfMachinekit))
+          gcode << "M2 ; end of program\n";
+    return gcode.str();
+}
+
 #ifdef SLIC3RXS
 REGISTER_CLASS(GCodeWriter, "GCode::Writer");
 #endif

xs/src/libslic3r/GCodeWriter.hpp

@@ -46,6 +46,7 @@ class GCodeWriter {
     std::string lift();
     std::string unlift();
     Pointf3 get_position() const;
+    std::string end_program();
     
     private:
     std::string _extrusion_axis;

xs/xsp/GCodeWriter.xsp

@@ -45,6 +45,7 @@
     std::string lift();
     std::string unlift();
     Clone<Pointf3> get_position() const;
+    std::string end_program();
 %{
 
 SV*