Make the list display customizable.

[Malabarba]

Not a priority, just here for future reference. The current question list is pretty, but people have different preferences. Ideally, there should be a variable somewhat like the following, which users could configure to get the display they want.

(defcustom stack-question-list-format
  '(score answers title newline "     " date tags newline)
  ""
  :type '(repeat (choice symbol string))
  :group 'stack-question-list)

Because, of the way tabulated-list-mode is designed, the newline part has to be done is a very hacky way, which is the only thing that makes this non-trivial.

[Malabarba]

Future note for myself. This will be much easier if we stop using tabulated list mode for the question list. That will require we reimplement some of its features, like the revert hook, but most of its features we no longer use anyway.