gmodeler: fix python export - main() is expected to be called with two arguments (#336)

gui/wxpython/gmodeler/model.py

@@ -2677,7 +2677,7 @@ if __name__ == "__main__":
         if properties.get('overwrite'):
             self.fd.write('    os.environ["GRASS_OVERWRITE"] = "1"\n')
 
-        self.fd.write('    sys.exit(main())\n')
+        self.fd.write('    sys.exit(main(options, flags))\n')
 
     def _writePythonItem(self, item, ignoreBlock=True, variables={}):
         """Write model object to Python file"""