Appropriate mobs not affected by darkness.

Gave the mobs, who shouldn't be affected by the darkness, the ability to see clearly in the darkness. These mobs include: AIs, Cyborgs and Xenomorphs.

Player feedback thread: http://ss13.eu/phpbb/viewtopic.php?f=12&t=891

Images for comparison.

Humans
![](http://i.imgur.com/dEnrQwG.png)

Cyborgs
![](http://i.imgur.com/IG6d0js.png)

Xeno (can only see 4 tiles in the dark)
![](http://i.imgur.com/rjIuh01.png)

AI
![](http://i.imgur.com/OMMEaNk.png)