Externalized html, added ability to redirect '/' when no hash or create command is sent.

Added ability to redirect '/' to a url or sub dir or file when no hash or create command is sent. 

Facilitates using this url shortener  as a stand alone website that redirects to the main site when a simple domain request is sent. But also supports redirecting to main/primary url or a static  dynamic site in a sub directory (or symlink).