Guide: guessing game promises number of guesses, but fails to deliver

[jkleint]

O, the heartbreak! ;)

https://github.com/rust-lang/rust/blame/master/src/doc/guide.md#L1749

@steveklabnik, not sure if you want to add a counter or remove the promise.

[steveklabnik]

Either works. I've done both versions. Probably just remove the promise.

[alexcrichton]

Closed by #17979