Please find bellow what i tested on a Pi2 with recent (december 2016) Raspbian image.
It is based on network manager and can be configured from command line.
You can change SFR by what you want.
websfr is my operator APN.
apt-get install network-manager # comment all in /etc/network/interfaces except lo related nmcli connection edit type gsm con-name SFR > print > set gsm.apn websfr > save > yes reboot