Fix: Calculated due to of todo lists doesn't update
requested to merge 476-incorrect-sorting-by-due-date-when-the-due-date-of-a-todo-list-changes-due-to-its-todos into stable
This fixes an issue where the shown due to which is derived from a todo within the list wouldn't be updated unless the page is forcibly reloaded (e.g. by changing into another page and then back).
Closes #476 (closed)