Features

• nuxt build -> Build only the application
• nuxt start -> Launch the server and nuxt (without building it, so make sure to launch nuxt build before)
• Add dev option to specify if the build will be for production or development, define also the webpack-dev-middleware and hot-reloading for nuxt-dev

Misc

• Refactoring some logic for webpack inside the webpack/*.config.js files
• Update README for production deployment
• Improve test with ava (checking the value of the color of the element)