Add a block to the update script to create default superuser

# Overview

Add a block of code that execs into the django container and creates a superuser for development. A [django superuser](https://docs.djangoproject.com/en/1.8/intro/tutorial02/) is a user that can view and edit objects and pages in the django admin. This account will be built with the application update and allow devs to see the backend data and manipulate it.

This user should only be created in the development build, not production
This user should have a generic username, fake email, and password and these attributes should be added to the setup instructions

# Context

Blocked by #5

# Suggested solution (optional)

[Superuser and admin tutorial](https://docs.djangoproject.com/en/1.8/intro/tutorial02/)

まずブロックされている issue #5 を確認し、次に update script と、それを実行する development-build path を特定します。Django container がどのように起動されるかを確認し、開発時のみの default account の動作を追加し、記載された credentials で setup instructions を更新します。production で account が作成されず、developers が Django admin を使用できれば完了です。

索引モデルが issue の本文から書いたものです。