[diff] copyright notice index.html

[Mischa]

Hi @tech,

Just noticed index.html still has 2017 in the copyright notice.

Mischa

Index: index.html
===================================================================
RCS file: /cvs/www/index.html,v
retrieving revision 1.726
diff -r1.726 index.html
7c7
<     <meta name="copyright" content="This document copyright 1999-2017
---
>     <meta name="copyright" content="This document copyright 1999-2018
138c138
<       <em>This site Copyright &copy; 1996-2017 OpenBSD.</em><br>
---
>       <em>This site Copyright &copy; 1996-2018 OpenBSD.</em><br>