Avoid memory leak.

src/interpreter.cc

@@ -230,13 +230,14 @@ PyObject* Interpreter::globals()
 void Interpreter::runPythonFile( std::string filename )
 {
   PyObject* pymainContext = globals_;
-  PyRun_FileExFlags(fopen( filename.c_str(),"r" ), filename.c_str(),
+  PyObject* run = PyRun_FileExFlags(fopen( filename.c_str(),"r" ), filename.c_str(),
              Py_file_input, pymainContext,pymainContext, true, NULL);
   if (PyErr_Occurred())
   {
     std::cout << "Error occures..." << std::endl;
     PyErr_Print();
   }
+  Py_DecRef(run);
 }
 
 void Interpreter::runMain( void )