r.plane: fix encoding issue for compiling winGRASS

git-svn-id: https://svn.osgeo.org/grass/grass/branches/releasebranch_7_0@71571 15284696-431f-4ddb-bdfa-cd5b030d7da7

scripts/r.plane/r.plane.py

@@ -1,5 +1,5 @@
 #!/usr/bin/env python
-#
+# -*- coding: utf-8 -*-
 ############################################################################
 #
 # MODULE:	r.plane for GRASS 5.7; based on r.plane for GRASS 5