Add hold-to-quit button for gameplay/replays #2430
Haven't worked on touch interface elements yet. Use this for now, will revisit the buttons again later.
To quit, player have to hold the button for 1s. "Hold to Quit" fades away after 5s. It's either "Quit" or "Resign", depends on the mode.
On hold, the action icon becomes bigger, "Hold to Quit" is visible again, and progress ring appears.
Looks ok to me
However I don't know what to do with this new HoldToQuit UI element during actual gameplay.