 [det]http_404(+Options, 
+Request)Reply using an "HTTP 404 not found" page. This handler is intended as 
fallback handler for prefix handlers. Options 
processed are:
[det]http_404(+Options, 
+Request)Reply using an "HTTP 404 not found" page. This handler is intended as 
fallback handler for prefix handlers. Options 
processed are:
- index(Location)
- If there is no path-info, redirect the request to
Location using http_redirect/3.
- Errors
- http_reply(not_found(Path))