Fixes #25.

Does what #25 suggests and extends from @typescript-eslint/eslint-plugin's recommended config. I then also added sub-configs specific to use cases:

• Emotion: @emotion/eslint-plugin
• Jest: eslint-plugin-jest
• JSX: eslint-plugin-jsx-a11y
• Lodash: eslint-plugin-lodash
• React (on top of JSX): eslint-plugin-react

Composable configs is a good practice allowing applications that don't meet all those use cases to not pull in rules they don't care about.

A consuming repo might include them with an ESLint config like:

{
  // ...
  "extends": [
    "@grafana/eslint-config",
    "@grafana/eslint-config/emotion",
    "@grafana/eslint-config/jest",
    "@grafana/eslint-config/jsx",
    "@grafana/eslint-config/lodash",
    "@grafana/eslint-config/react"
  ],
  // ...
}

Finally, this wipes all the rule settings out index.js, then adds back any rule settings that change the default value.

See grafana/grafana#56240 for an example of pulling this in.