Add more stats for country guessing #1260

@juanignaciosl can you please review? thanks!
The thing is that all ruby expressions returns something and it is nil if nothing else is specified. I only made explicit that the method does nothing but I can remove the nil if you feel more confident that way.

A  snippet to illustrate my point:
```ruby
def returns_nothing; end

def returns_nothing_as_well
  nil
end

p returns_nothing
p returns_nothing_as_well
p returns_nothing == returns_nothing_as_well
```
prints out this:
```
nil
nil
true
```

Shall I change it? I really don't mind changing it :)