Updated further Coin links

Author: VolkerEnderlein

docs/index.html

@@ -15,9 +15,9 @@ <h1>Internet Links</h1>
 
 <ul>
 <lh><large><b>Directly Related Links</b></large></lh>
-<li><a href="http://coin3d.github.io/SoXt/">SoXt Documentation</a> generated with Doxygen.
-<li><a href="http://coin3d.github.io/Coin/">Coin Documentation</a> generated with Doxygen.
-<li><a href="http://coin3d.github.io/">coin3d.github.io</a>
+<li><a href="https://coin3d.github.io/soxt/">SoXt Documentation</a> generated with Doxygen.
+<li><a href="https://coin3d.github.io/coin/">Coin Documentation</a> generated with Doxygen.
+<li><a href="https://coin3d.github.io/">coin3d.github.io</a>
 <li><a href="http://www.tgs.com/Support/Documentation/3DMS/index.html">TGS on-line Open Inventor documentation</a>
 </ul>