OurCar means "our car to success"
- clone the main repository
~> git clone https://github.com/mazhao/ourcar.git
- initialize all the submodules
~>cd ourcar
~>git submodule init
~>git submodule update
- open workspace
~>open ourcar.xcworkspace
~>cd ourcar
~>git checkout master
~>git pull
~>cd ..
~>git commit -am "Pulled down update to submodule_dir"