Redoing shift and daily goal logic (part 1)

Admins asked for way to change shifts and work goal per day instead of
per week. So, let’s go.

Butchering models, still thinking about how to do migrations and views.
Redoing shift and daily goal logic (part 2)

UI changed, migrations added, some dumb bugs fixed, just need to
actually test it and check if it works
Redoing shift and daily goal logic ([hope-to-be] finish)

Views working fine, last fixes on models, last fixes on report
generator, unless I missed something is done now.