Port tester to verify connectability

[foobarlab]

Either at the backend or during loading a stage a "port testing facility" would be useful to quickly sort out connection problems.

Ports to be tested (standard port in brackets):

• Web-Port (8081, probably also 80)
• Swf-Port (7230)
• Policy-Port (3000, fallback to 843, 80)
• RTMP (1935, but could also scan all stream servers and check availability)