Correct tests

I launch the init.d script in the test to be able to check service.
Unfortunately I can't test ports as influxdb don't start enough quickly.
What about upstart / systemd / ...?

exec `/etc/init.d` never be the way to do for major distrib.
* on rhel: `service myservice start`
* on debian: `invoke-rc.d myservice start` and now `service myservice start` will be working too.

My 2 cents ;)