Update instructions to specify the need for a pypi account

[jlillest]

• Date you used Cookiecutter DjangoPackage: today
• Cookiecutter version used, if known:
• Python version: 3.4
• Operating System: linux

Description

Offering a suggestion to update the instructions to specify a need for a pypi account. I used cookiecutter today to push my first django package to pypi and I got stuck on the register and publish steps, as it would allow me to register without any warnings or account and then spent lots of time wondering why I couldn't publish.

Also, I found this info on the pypirc file very helpful:
pipyrc documentation

Thanks for the great tool, it saved me hours overall!