Add a “replay” to the reviewer’s menu.

As @dae has noted in relation to PR #278:
> AnkiMobile provides a global replay button as an assignable action or from a menu, so by default users only see the embedded buttons

So here is a menu item that replays all files.

To do the replay i added a switch to Reviewer.playSounds() to ignore the autoplay setting at the right times. That should make "play sound' gestures work, too, when autoplay is off.

It  makes the "replay question, too" setting independent of the "autoplay". That seems like the Right Thing when there is a way to replay audio.

(And my emacs automatically nixes trailing whitespace.)