Osu: Add hold esc for menu in options.

[LovelyA72]

I asked some of my friends about this new feature. Most of them said it will be a little bit hard for old players to get used to this behavior. And it might causes note missing(or level fail). If there's a switch in options menu that can enable/disable this feature,it will be better.
Concern from #3686

[peppy]

The addition of this is to dissuade pausing. We may add hotkeys to quick exit (like quick retry) to alleviate this.

[jorolf]

How would you implement that button?
Just a single press quitting the player? Hold to quit? Maybe double tap?

• A single press to quit is way to easy to hit accidentally (with pause this wasn't that much of an issue because you could continue)
• Hold to quit is exactly what we're trying to bypass in the first place
• Double tap seems like a good alternative but it is quite hidden for new/old players, you would have to mention that somewhere specifically

[peppy]

Hold to quit, yes.

[LovelyA72]

I think there needs to have at least one way to instantly stop the current level instead of holding a key.