Print precheck errors

[christianabila]

Hi from Purkersdorf, Austria!

I would find it helpful to have the result of the restore precheck checked and the errors printed (classes/task/restore_courses.php:159).

It would make debugging faulty runs of the scheduled task easier.

Thanks,
Chris

[abias]

Hi @christianabila ,

thank you very much for this proposal. This is a nice idea which could be really useful. Would you be able to come up with a pull request?

Thanks,
Alex

[christianabila]

Hello! I'll see if I may put it on my work schedule. Will get back to you.