- hostname.if can handle lladdr as well as if names now

- hostname.if can handle lladdr as well as if names now
- mention that they can be used for dynamic addressing
- lower the reading order of multicast routing (it makes sense to place
this at the end)
- Xr route(8) up front of the route text, not the end
- use Xr rather than Pa where possible
- reorder the forwarding text