This example demonstrates the automatic routing table configuration features of
the IPv4NetworkConfigurator. There are two networks in the example. The first
one focuses on the basic settings, one by one. The second one demonstrates the
IPv4NetworkConfigurator features on a complex network that contains both wired
and wireless nodes.

In the simple example, there are 4 nodes connected with each other in a square.
Each node sends ping packets to all interfaces. Each configuration section
demonstrates a single automatic routing table configuration feature. 

In the complex example, there are two completely separate wireless networks and
some wired nodes. The source node sends ping packets to the wireless and wired
interfaces of the destination node. The routing tables are set up in the following
way. The ping packets reach the wireless destination interface while going
through both wireless networks and one shared wired link. On the other hand, the
ping packets reach the wired destination interface using only wired links,
including the shared wired link.