Fix bad faction colour only being applied to uninhabited

This applies the fix suggested in #2380, thus it only fixes faction colour of star name, not faction colour in zoom out view.

(For testing, rememer: Shift+arrow for fast movement in sector view)

Unexplored system name turns up as yellow:
![screenshot-20140808-130402](https://cloud.githubusercontent.com/assets/619390/3855884/816b57ac-1eec-11e4-8a55-803679dd6cfd.png)


This PR unexplored system name turns up as gray:
![screenshot-20140808-130145](https://cloud.githubusercontent.com/assets/619390/3855883/7deecf00-1eec-11e4-8bf3-2bcabf77c229.png)