Add link to ML instructions

Close php#759

Author: saundefined

Diff for: contact.php

@@ -56,7 +56,7 @@
 <p>
  If you would like to contact the webmasters for some other reason, please
  write to <a href="mailto:[email protected]">[email protected]</a>.
- Note that this address is mapped to a mailing list and a newsgroup, so
+ Note that this address is mapped to a <a href="/mailing-lists.php">mailing list</a> and a newsgroup, so
  <strong>every message you send will be stored in public archives at multiple
  servers</strong>.
 </p>