Consider making wpa_supplicant.conf chmod 600

[nolim1t]

In case of publically available boxes (especially with deploy keys being shared). Risk is low-medium now but it should be addressed.

https://github.com/lncm/pi-factory/blob/864f5b8fd4499925b4adf83ac0441a0f4717dadc/etc/init.d/wpa_supplicant#L16