Improve behavior when network is interrupted (e.g. laptop sleeps)

• Improve behavior when network is interrupted (e.g. laptop sleeps) by

using a fixed delay instead of fixed rate

• Improve the discovery results reading
• refactor the messages sending to allow better unit testing (separate

the content determination from the sending)

• Removed one findbugs warning/ nullpointerexception when no reply from

cube is coming

Signed-off-by: Marcel Verpaalen <marcel@verpaalen.com>