Install instructions fail to mention that git 1.7.10 is required

Created by: spuder

Summary - Users are likely to assume any version of git will work, however git 1.7.10 or newer is a requirement. I find the most recent version provided in many ubuntu repos is 1.7.9.5

Steps to reproduce - Install gitlab an ubuntu 12.04 system. Install git with apt-get install git-core

When you run the command sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production, you will get the following error

Init script up-to-date? ... yes
Projects have satellites? ... can't check, you have no projects
Redis version >= 2.0.0? ... yes
Your git bin path is "/usr/bin/git"
Git version >= 1.7.10 ? ... no
  Try fixing it:
  Update your git to a version >= 1.7.10 from 1.7.9
  Please fix the error above and rerun the checks.

Checking GitLab ... Finished

Expected behavior - The instructions should clarify that git 1.7.10 or newer is required. Ideally it would give instructions on how to install the latest version of git. https://launchpad.net/~git-core/+archive/ppa