Update commands doc.
Update commands doc.

The current Makefile template doesn't use `s3cmd` anymore but `aws s3 sync`.
ScottSnapperLab/cookiecutter-data-science,mnarayan/cookiecutter-data-science,uberwach/cookiecutter-kaggle,drivendata/cookiecutter-data-science,drivendata/cookiecutter-data-science,grenzi/cookiecutter-data-science,ScottSnapperLab/cookiecutter-data-science,ScottSnapperLab/cookiecutter-data-science