use github_document format
diff --git a/.Rbuildignore b/.Rbuildignore
index 333d2c4..406b496 100644
--- a/.Rbuildignore
+++ b/.Rbuildignore
@@ -1,6 +1,6 @@
 ^.*\.Rproj$
 ^\.Rproj\.user$
-README.md
+README.*
 examples/