message: docs: add code quality badge
diff: [![Build Status](https://travis-ci.org/danielcondemarin/serverless-nextjs-plugin.svg?branch=master)](https://travis-ci.org/danielcondemarin/serverless-nextjs-plugin)
  [![npm version](https://badge.fury.io/js/serverless-nextjs-plugin.svg)](https://badge.fury.io/js/serverless-nextjs-plugin)
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  A [serverless framework](https://serverless.com/) plugin to deploy nextjs apps.
  