remove check for "human_ai"

"human_ai" doesnt exist anymore so we can remove this check.
fix windows build
don't generate "user_description" on the host

the host it not capable to generate strings in the correct language.
("(Reserved for $playername)" was resolved on the host). Instead we now
generate the description on the clients.
simplify "save_id" generation

By having one place instead of three where this happens. Also the previous code was bugged becasue it used "saved_id"