Add scenario test for port forwarding and UDP

This test extends exisiting port_forwarding scenario test which
was only configuring and testing port forwarding to 2 different
servers using TCP protocol (by SSH to those instances to different
ports).

Now it also creates UDP port forwarding, spawns nc on each VM
and tries to connect to this nc and check if it will return proper
message from each VM.

Change-Id: I3afd877521e7cf66a8970f531111b3e1b1e7b150
2 files changed