Added entries for re, soundex modules.
diff --git a/Doc/lib/libstrings.tex b/Doc/lib/libstrings.tex
index ec4834b..411e415 100644
--- a/Doc/lib/libstrings.tex
+++ b/Doc/lib/libstrings.tex
@@ -8,6 +8,9 @@
\item[string]
--- Common string operations.
+\item[re]
+--- New Perl-style regular expression search and match operations.
+
\item[regex]
--- Regular expression search and match operations.
@@ -20,4 +23,7 @@
\item[StringIO]
--- Read and write strings as if they were files.
+\item[soundex]
+--- Compute hash values for English words.
+
\end{description}