Project initialization environment improvements

[ryangallen]

• Update default cookiecutter values; use random password/secret values
• Store environment secrets in .env file
• Automatically initialize git repository
• Add .gitattributes and .gitignore files
• Add cookiecutter links to project README
• Remove application secrets from source code; read from environment variables
• Change user crud get functions to use one_or_many()
• Fix frontend errors by casting to String

[Buuntu]

This is a lot of changes for a pull request. Can you open a discussion first and link to it? Some of these seem like good ideas but I'd rather approve them individually after some thought instead of in one go. This is a lot for a single pull request imo