Resolve FIXME of using interfaces instead of hardcoding URIs:
- Notice: This changes some of the form names which is a safe thing to do - AFAIK they are merely cosmetic. And the forms still work for me.
- The createIdentityURI wasn't being used anymore, can be removed.
- For being really safe, the URI construction mechanism in IdentityPage HAS to be that complex :| See http://stackoverflow.com/questions/10330138/java-net-uri-resolve-against-only-query-string