Whenever you do

sudo apt-get install git-core

on Ubuntu you will only get git version 1.7.5.x. I needed 1.7.6%2B.

To do this you have to run the following commands:

sudo apt-get install software-properties-common python-software-properties
sudo add-apt-repository ppa:git-core/ppa
sudo apt-get update
sudo apt-get install git-core

This should give you git version 1.7.11 (as of today)