Freestyle: use bool instead of int.

Patch contribution by flokkievids (Folkert de Vries).  Thanks!

source/blender/freestyle/intern/python/BPy_Interface0D.cpp

@@ -103,7 +103,7 @@ static int Interface0D_init(BPy_Interface0D *self, PyObject *args, PyObject *kwd
 	if (!PyArg_ParseTupleAndKeywords(args, kwds, "", (char **)kwlist))
 		return -1;
 	self->if0D = new Interface0D();
-	self->borrowed = 0;
+	self->borrowed = false;
 	return 0;
 }