Wait longer for Instruments to launch when retrying

Subliminal script originally waits 30 seconds when launching
Instruments and the app. If nothing has been written after these 30
seconds, the Simulator is killed and it tries it all again — if the
retry count limit has not yet been reached.

In older machines, 30 seconds may not be enough for Instruments and the
app to launch. Let’s implement a sort of exponential fall back and
increase the timeout duration after each try: 30 seconds, 45 seconds, 1
minutes and then 2 minutes.
Insert a blank line after the "GUI is not authorized" alert message
Merge pull request #120 from inkling/nanouk/wait-longer-instruments-launch

Increase timeout duration for Instruments to launch