Add print view with all print views combined

[dboehmer]

It's tedious to click all day plans and purchase lists and print each one.

Add a form to select days and purchase lists to display and render a page with all of them.

Important: use CSS page-break-before to split the lists on different pages as when they were rendered seperately. https://developer.mozilla.org/en-US/docs/Web/CSS/page-break-before