Update authors

Fishtest is a key factor of SF success.

Thanks to Fishtest we have not only greately
improved ELO but, even more important, we
have enabled a kind of joint development and
testing that it is the herat of on open
source project like SF.

Open sourcing is not just about open code, it is
about commuity development. In case of a chess engine
this has never been possible before due to missing
a strong and strict testing environment that allows
many people to contribute in a safe and coordinate way.

Fishtest is a new way of developing chess engines,
something that has never exsisted before.

No functional change.