Wait for the services before ending the start daemon action to prevent i...

...ts usage before being ready

I did some testing and I found that with a check like: https://github.com/Zentyal/qa/blob/a4aa186f808388c1eb0b6335c3d1b812c7966467/server-tests/tests/users/standalone/restart-users the issue raised on ticket trac.zentyal.org/ticket/3407 may be reproduced. It's not happening always, in fact I was able to reproduce it only with a 3.2 server and after a while, I'm not able to get it failing again, so I guess it depends on a timing issue and a cache is preventing me to get it failing again.

Anyway, making sure that the service is fully started before ending the script shouldn't be an issue.

Maybe for 3.3 we should add this kind of check on by default for all our services, since its introduction on 3.2 for samba seems like that fixed many problems after a restart.

The code at UsersAndGroups.pm would be refactored a bit to reuse the $self->_services method in places like initialSetup, however I choose not to do it given it's an stable release and I wanted to be as less intrusive as possible.