Better TAB key handling in fiplr-find-file

[mcandre]

As a former dired user, I want fiplr-find-file to autocomplete the search term on TAB key, setting it to the highlighted result, so that fiplr feels more intuitive.

Currently, pressing the TAB key during fiplr-find-file appends a literal \t tab to the search term, making the results empty.

As a workaround, I configure my fiplr to drop the TAB key:

(define-key *fiplr-keymap* (kbd "TAB")
  (lambda ()
    (interactive)))

But I'd really like fiplr/grizzl to set the minibuffer search term to *grizzl-current-result* on TAB.