Remove all uses of \sectcode; we can now use logical markup everywhere.
diff --git a/Doc/lib/libregex.tex b/Doc/lib/libregex.tex
index 6582c72..0c216d2 100644
--- a/Doc/lib/libregex.tex
+++ b/Doc/lib/libregex.tex
@@ -1,4 +1,4 @@
-\section{Built-in Module \sectcode{regex}}
+\section{Built-in Module \module{regex}}
 \label{module-regex}
 \bimodindex{regex}