List items that will be invoiced next
This feature request consists of two tables.
On the overview page (or the 'to be invoiced' tab), there will be a table, that shows the upcoming invoices.
It will show the next invoices: monthly, quarterly etc.
This is to confirm that billing is correctly set up for the client, but also to inform the client, when asked.
On the admin dashboard / forecast page there will a table that shows all upcoming potential invoices (if nothing is changed). Currently the forecast page just shows amounts, but this way it will be possible to see where a big (or small) amount/change is coming from.