Internet on FIRE

Timers: Fix TBF and some last remains

OSPF: Update to new timers

Note that recurrent timers are currently limited to ~1 hour.

Timers: Replace old timers with microsecond timers

The old timer interface is still kept, but implemented by new timers. The
plan is to switch from the old inteface to the new interface, then clean
it up.

OSPF: Fix minor issue in TTL check

The TTL check must be done after instance ID dispatch to avoid warnings
when a physical iface is shared by multiple instances and some use TTL
security and some not.

OSPF: Support of address families in OSPFv3

OSPFv3-AF can handle multiple topologies of diferent address families
(IPv4, IPv6, both unicast and multicast) using separate instances
distinguished by instance ID ranges.