Remove all uses of \sectcode; we can now use logical markup everywhere.
diff --git a/Doc/lib/libimghdr.tex b/Doc/lib/libimghdr.tex
index bf1c0ef..d624f06 100644
--- a/Doc/lib/libimghdr.tex
+++ b/Doc/lib/libimghdr.tex
@@ -1,4 +1,4 @@
-\section{Standard Module \sectcode{imghdr}}
+\section{Standard Module \module{imghdr}}
 \label{module-imghdr}
 \stmodindex{imghdr}