Feature request: allow specifying default options

[Kamilcuk]

In my server configuration, everything should be protected by auth=kamil and only accessible from specific ip address allow=ip:myip. Would be great, if I would be able to set route add defaults auth=kamil allow=ip:myip in the route config or inside configuration like route.opts.defaults="auth=kamil allow=ip:myip", so that it would be applied by default on all the routes except when nullified auth= allow=. Thanks for making fabio, it is great.