I have configured a copy of the piaware-3.1.0 image with all the things needed to use wi-fi, except your wifi ssid and matching password. The image has already undergone an apt-get update and apt-get upgrade as of 10/3/16, so the O/S is up to date of of then.
All you need to do is to run the command:
sudo wpa_passphrase (your ssid) >> wpa_supplicant.conf [Enter]
(your ssid password) [Enter]
from within /etc/wpa_supplicant
and then run the command:
ifup wlan0 [Enter]
You can download the image from here: dl.dropboxusercontent.com/u/962 … g-wifi.img
Download the image, and burn it to an SD card (micro, of course), and then boot your pi, then run the commands above, and you should be all set.
If you have any questions, feel free to pm me.