Improvement to charset docs

This just adds a link to the pattern_ops operator class section from the
part of the locale docs that mentions that indexes don't work for LIKE
under a non-C locale.

(untested)

Chris
Index: doc/src/sgml/charset.sgml
===================================================================
RCS file: /projects/cvsroot/pgsql/doc/src/sgml/charset.sgml,v
retrieving revision 2.69
diff -c -r2.69 charset.sgml
*** doc/src/sgml/charset.sgml    14 Mar 2005 18:31:19 -0000    2.69
--- doc/src/sgml/charset.sgml    15 Mar 2005 01:55:10 -0000
***************
*** 224,229 ****
--- 224,236 ----
      from being used by <literal>LIKE</>. For this reason use locales
      only if you actually need them.
     </para>
+
+    <para>
+     As a workaround to allow <productname>PostgreSQL</> to index
+     <literal>LIKE</> under a non-C locale, several custom <link linkend="indexes-opclass">operator classes</link>
+     exist that allow a strict character-by-character comparison, ignoring
+     locale comparison rules.
+    </para>
    </sect2>

    <sect2>