Fix markup for tilde in URL.

Doc/inst/inst.tex

@@ -977,7 +977,7 @@ for Distutils (see section~\ref{config-files}.)
     {Information about the free \Cpp{} compiler from Borland,
      including links to the download pages.}
 
-  \seetitle[http://www.cyberus.ca/~g_will/pyExtenDL.shtml]
+  \seetitle[http://www.cyberus.ca/\~{}g_will/pyExtenDL.shtml]
     {Creating Python Extensions Using Borland's Free Compiler}
     {Document describing how to use Borland's free command-line C++
      compiler to build Python.}