Add a custom rule to prevent colors from being hardcoded outside of theme (#288)

* Add a custom rule to prevent colors from being hardcoded in ESLint

* Refactor colors

* Create packages folder and fix colors

* Remove external dependency for css alphabetical order linting

* Fix install with yarn

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Co-authored-by: Charles Bochet <charles@twenty.com>

front/README.md

@@ -6,7 +6,7 @@ This project was bootstrapped with [Create React App](https://github.com/faceboo
 
 In the project directory, you can run:
 
-### `npm start`
+### `yarn start`
 
 Runs the app in the development mode.\
 Open [http://localhost:3000](http://localhost:3000) to view it in the browser.
@@ -14,12 +14,12 @@ Open [http://localhost:3000](http://localhost:3000) to view it in the browser.
 The page will reload if you make edits.\
 You will also see any lint errors in the console.
 
-### `npm test`
+### `yarn test`
 
 Launches the test runner in the interactive watch mode.\
 See the section about [running tests](https://facebook.github.io/create-react-app/docs/running-tests) for more information.
 
-### `npm run build`
+### `yarn build`
 
 Builds the app for production to the `build` folder.\
 It correctly bundles React in production mode and optimizes the build for the best performance.
@@ -29,7 +29,7 @@ Your app is ready to be deployed!
 
 See the section about [deployment](https://facebook.github.io/create-react-app/docs/deployment) for more information.
 
-### `npm run eject`
+### `yarn eject`
 
 **Note: this is a one-way operation. Once you `eject`, you can’t go back!**