Add "dos" to EXTRA_DIST.
diff --git a/Makefile.am b/Makefile.am
index f20897d..dcbecef 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -32,6 +32,7 @@
 	Doxyfile.in \
 	extra \
 	doc \
+	dos \
 	windows \
 	COPYING.GPLv2 \
 	COPYING.GPLv3 \