Link to Arbor examples on the "advanced mode" homepage

[curtislisle]

The main page of this app, is actually the "advanced mode" according to the biologists. We need to have some links to documentation pages added here. This may be something we do at the Arbor customization level, if we separate the tangelohub and arbor repositories, as this isn't needed for "tangelohub" instances used for non-biological purposes.