Test: Updated lifecycle tests.
Examples: Renamed IPv4NetworkConfigurator submodules to configurator.
ARP: Fixed when there's no IP address during initialize.
TCPBasicClientApp: Fixed socket closing during shutdown.
UDPBasicApp: Added check to skip unresolved destination addresses in.
UDPSink: Added some text output for testing.
IPv4NetworkLayer: Added IPv4NodeConfigurator.
TODO