global settings and currency name

[yoel123]

global settings would be a hashmap inside game_manger.

the first one will be currency name, to give the player the ability to name the currency something else rather than credits (this is a luxury feature obviously).

the player might want to call the currency :drahma, dolla,chips,shekels, bananas, cats, latinum, moneh,gold or whatever.

not much of an effect on gameplay but its sort of customization maybe add a station name too.,