Remove all uses of \sectcode; we can now use logical markup everywhere.
diff --git a/Doc/lib/libstring.tex b/Doc/lib/libstring.tex
index c7889c9..6df547e 100644
--- a/Doc/lib/libstring.tex
+++ b/Doc/lib/libstring.tex
@@ -1,4 +1,4 @@
-\section{Standard Module \sectcode{string}}
+\section{Standard Module \module{string}}
 \label{module-string}
 \stmodindex{string}