Without argument, simply evaluate if the faction is controlled by a human (or semi-human in case of some testers out there :siffle
.If NOT, does the reverse, ie the condition is true if the faction is computer-controlled.
Reminder about CheckAILevel ... It works by testing if AI level is equal or superior to the value you give, with 0 being human, 1 easy AI and so on. So in effect, you can't check if the given faction is an human (and not an AI): you can only check if it is an AI with such one.
