Adds link to Chinese translation from front page, closes #2903

Author: JJ

doc/HomePage.pod6

@@ -54,6 +54,9 @@ Perl 6 compiler developers may also be interested in
 Documentation for the different but related <a href="https://www.perl.org/">Perl 5</a> language
 can be found on the <a href="http://perldoc.perl.org/">Perl 5 documentation website</a>.
 </p>
+
+<p>Part of this official documentation has been translated into Chinese. Here's the <a href='https://github.com/ohmycloud/perl6doc-zh/blob/master/index.adoc'>index to the pages that have been translated</a>.</p>
+
 =end Html
 
 # vim: expandtab softtabstop=4 shiftwidth=4 ft=perl6