Added "distclean" target to the Makefile, which is expected by the
scripts handling automatic updates to the tarball and website.
diff --git a/Makefile b/Makefile
index 02000c3..9f28a08 100644
--- a/Makefile
+++ b/Makefile
@@ -79,3 +79,7 @@
 veryclean:
 	for tech in ${TECHS}; do \
 		${MAKE} veryclean-$${tech}; done
+
+distclean:
+	for tech in ${TECHS}; do \
+		${MAKE} veryclean-$${tech}; done