I’m not sure if the tutorial you are following has been tested with the Galileo Board, I suggest you to contact Adafruit to know if they have tested his tutorial with the Galileo Board, this is because it seems to be oriented only to the boards: Raspberry Pi and Beaglebone Black [http://www.adafruit.com/support - http://www.adafruit.com/contact_us]
What is the output of running uname -a?
The Yocto image uses opkg and not apt-get so you must install your packages in a different way. I saw you are using Alext’s repo (I’m assuming you are using the uClibc image, is this right?)
The errors you are getting after running opkg update are due to the network connection.
How are you setting your internet connection?
Are you using a WiFi module or are you using Ethernet?
Could you post your wpa_supplicant.conf file?
What is the output of running ifconfig?
Are you able to ping a website?
About the opkg install python-pip, I just checked the repo and I didn’t find this package (http://repo.opkg.net/galileo/i586/)
Follow the instruction in here: http://pip.readthedocs.org/en/stable/installing/ to install pip in the board.
Then, try to install PyOpenSSL and oauth2client.
sorry for replying so late, I was busy preparing for the exams last week.
Anyway, you were right, I got the internet connection fixed, changed pip and had required packages downloaded.