Documented supported browsers.

docs/index.html

@@ -23,7 +23,9 @@
 
   <p>
     The library is developed by
-    <a href="http://almende.com" target="_blank">Almende B.V.</a>
+    <a href="http://almende.com" target="_blank">Almende B.V.</a>.
+    Vis.js runs fine on Chrome, Firefox, Opera, Safari, IE9+, and most mobile
+    browsers (with full touch support).
   </p>
 
   <h2 id="Components">Components</h2>