* Get rid of the base classes Rule and Leaf_rule,
* Make log output about initiated or invalid routing rules conform to the rest
of the router log, and
* Ensure that each type of routing rule when being invalid invalidates its
whole domain.
Issue #2840
The router reacts as follows to a configuration change:
1) Construct new internal configuration representation (the old one stays
in place to be able to do comparisons in the following steps)
2) Iterate through all user-dependent objects (interfaces, link states, ARP
information, DHCP information) and re-check which remain valid with the
new configuration and which must be dismissed.
3) Adapt the objects that remain valid to the new configuration (re-write
references) and remove or detach the dismissed objects.
4) Do a link state DOWN at each interface and a link state UP at each
interface that remains attached to a domain.
5) Replace the old internal configuration representation with the new one
This way, the router keeps as much user dependent states as possible
while going through a configuration change. Thus, overwriting the old
configuration with an exact copy of itself is (almost) transparent to
clients of the router. Almost, because there are things the router must
do on every configuration handling, like re-scheduling the expiration
timeouts of links.
Ref #2670
