Add `repeat_header` LaTeX option for #13
add the tests folder to build ignore to reduce the size
diff --git a/.Rbuildignore b/.Rbuildignore
index 4952b99..8128b14 100644
--- a/.Rbuildignore
+++ b/.Rbuildignore
@@ -1,3 +1,4 @@
 ^.*\.Rproj$
 ^\.Rproj\.user$
 ^docs$
+^tests$