New section header style.

Fix up a few synopses.
diff --git a/Doc/lib/libregsub.tex b/Doc/lib/libregsub.tex
index 0a75f36..b779193 100644
--- a/Doc/lib/libregsub.tex
+++ b/Doc/lib/libregsub.tex
@@ -1,4 +1,5 @@
-\section{Standard Module \module{regsub}}
+\section{\module{regsub} ---
+         Substitution and splitting operations that use regular expressions.}
 \declaremodule{standard}{regsub}
 
 \modulesynopsis{Substitution and splitting operations that use regular expressions.}