VDEv2: Virtual Distributed Ethernet.

Components of the VDE architecture:
- VDE switches: virtual counterpart of ethernet switches.
- VDE cables: virtual counterpart of a crossed-cable used to connect two
  switches.

- VDE 2 includes:
- switch management both from console and from a "unix socket terminal"
- VLAN 801.1q *almost* compatible
- FSTP (fast spanning tree) already incomplete and currently not tested for
  802.1d/w/s compatibility. under development. (vde_switch must be compiled
  with the FSTP flag on)
...
