Update API documentation link

Author: twiss

index.html

@@ -48,7 +48,7 @@ <h2>Resources</h2>
     <ul>
       <li><a href="https://github.com/openpgpjs/openpgpjs" target="_blank">Source code</a></li>
       <li><a href="https://github.com/openpgpjs/openpgpjs/blob/master/README.md#getting-started" target="_blank">Getting started</a></li>
-      <li><a href="openpgpjs/" target="_blank">API documentation</a></li>
+      <li><a href="https://openpgpjs.github.io/openpgpjs" target="_blank">API documentation</a></li>
       <li><a href="https://github.com/openpgpjs/openpgpjs/issues" target="_blank">GitHub issues</a></li>
       <li><a href="https://github.com/openpgpjs/openpgpjs/wiki" target="_blank">Wiki</a></li>
       <li><a href="https://twitter.com/openpgpjs" target="_blank">Twitter</a></li>