Implement `eslint --init`

[Toru Nagashima]

People can set up ESLint for their project with eslint --init command. The command installs eslint and necessary plugins into the project local.

However, eslint-cli requires local-installed ESLint to use eslint --init. This is inconvenient.

$ eslint --init
Cannot find local ESLint!
Please install ESLint by `npm install eslint --save-dev`.

🤔 though I ran eslint --init to install ESLint locally....

[唯然]

This package is no longer necessary. Use the built-in npx command instead.