Log from IPv4NetworkConfigurator is useless

[avarga]

It is impossible to get a useful summary on what IPv4NetworkConfigurator actually did. For one simulation, IP addresses were not configured; when tracking down the problem, the default initialize() log messages from IPv4NetworkConfigurator helped absolutely nothing. Turning on EV_DEBUG was also useless: it printed lots of lines but without context, i.e. it prints things like "Selected interface address: 10.0.0.38" -- but to which interface??? Turning on dumpAddresses is also useless, because it prints on InterfaceEntry::info() and NOT the addresses computed by the configurator (those computed addresses may or may not be actually set on the interfaces!)

Output should be made useful: by default it should print summary info (computed <N> addresses for <N> interfaces on <N> links etc). EV_DEBUG output should be made more structured (use indentation!) DumpAddresses should print not only the ie->info() but also the assigned addresses!

Issue migrated from http://dev.omnetpp.org/bugs/view.php?id=673