Add a test framework for the ospfd routing daemon.  For each test
one fresh daemon is started with an individual config.  It is talking
OSPF via a tun interface.  At the process side of the tun device a
client is running.  This test programm is parsing the OSPF packets
and generates new ones.  It simulates other OSPF daemons.

For now only hello packets are tested.  Each test has a task list
which drives the ospfd through its interface state machine.  The
plan is to extend the framework for the other OSPF packet types and 
state machines.  Eventualy the generated kernel routing messages 
could also be checked.

I have developed this test suite together with Florian Riehm.