Switch to using dotenv instead of yaml configuration files

[nuclearsandwich]

YAML config files are difficult to maintain and grow and present challenges with managing configuration through local development and production environments.

According to the 12 Factor Application, configuration belongs in the Environment rather than in settings files. Heroku uses environment variables as the Application-facing interface to the heroku config command.

This PR will start us out using a gem called dotenv to load environment variables needed in development from a file called .env in the application directory.

This file will be ignored by Git so that each individual contributor's specific development configuration is not overwritten by changes made by others.

To start off new developers a bootstrapping script will be created which sets up a local development environment in as few manual steps as possible.

Ready status 🚥

• Include dotenv-rails gem
• Add .env to .gitignore
• Write script/bootstrap program
• Update README with new bootstrap instructions
• Test on Mac OS X / Linux
• Test on Windows
• Remove config/database.yml from repository.

[nuclearsandwich]

@iTweak0r do you still do Rails development on Windows? I might stop trying to make this cross platform right away and work on it later.

[nuclearsandwich]

Added some really basic developer docs https://github.com/CoderDojoSV/CoderDojoSV-2.0/blob/long-live-dotenv-down-with-yaml/docs/development.md