This is useful for static locals that never need to be destroyed:
Thing& Thing::the()
{
static Eternal<Thing> the;
return the;
}
The object will be allocated in data segment memory and will never have
its destructor invoked.
Choosing adapter for transmit is done by adapter_for_route_to(IPv4Address).
This is just hard-coded logic right now but can be expanded to support a
proper routing table.
Also start moving kernel networking code into Kernel/Net/.
