Generic fixes

* Remove dead pods. Now 10 pods listed in the order of most monthly users from pods.jasonrobinson.me.
* Fix branding - 'diaspora*' is the correct styling.
* Add favicon here that used to be pulled from joindiaspora.com
* Fix sharing code examples according to comments from Cyprien Pouzenc. Basically moving the javascript from href to onclick avoids a blank page with [object Window] in some cases.

Mind these in one pull? ;) I assume index.html needs to be minified for things to work - any tips on what you've used or you want to do it - assuming these changes are ok?