Send email to digIT when things are about to break

[ViddeM]

Hubbit breaks in different ways when there is no study_period or study_year for the current date.

This is solved by manually inserting these into the database and is often forgotten about. Since study period dates are not standardised, it is surprisingly difficult to automate this (hence the current system).

It would, however, be nice if an email was sent to digIT before things broke instead of it being done after things break and people complain to digIT. goldapps is a nice service that can be used for this purpose <3