Feature request: Add option to delete all checked items in a list

[bertramrichter]

I am very enjoying the app so far.
And I like my lists as tidy as possible, so I find myself often selecting all items, that are checked (that is, already bought) to remove by hand.
A button added to the delete menu either to directly remove checked items or just to select them for removal would be very helpful in this regard.

Thanks for your time and effort. Keep it up, it's highly appreciated.