Draft: Containernet Topology-Demo

This commit contains the new Containernet Demo.

I kept roughly the same CLI as my standalone demo and appended a small README section on how to set things up in the demo folder. Also cleansed my existing demo by some nasty code...

This branch also contains the latest changes from the forwarding branch:

• Removed duplicated code in interface.rs probably caused by a weird merge
• Fix panicking if we receive messages with bogus scope_id 0 (Not sure where they come from yet. I just ignore them)
• Create required forwarding interface KIRA in the Daemon itself (handled transparently by NativeFwdTable)
• Add forwarding IPs (fc00::node_id) to interfaces by utilizing the already existing (and by now unused) PNetInterfaceMonitor:
  1. Hook in main.rs which adds IP to interfaces as they come up
  2. Refresh monitor as we broadcast, since we need to know the current available interfaces at that moment (only ll-broadcast in IPv6)