promisify'd version of mkdirp using bluebird and mkdirp as peerDependencies.
// mkdirp and bluebird are peerDependencies. You don't need to install them if you already use them in your projects
npm install --save mkdirp bluebird bluebird-mkdirp
const mkdirp = require('bluebird-mkdirp');
mkdirp(dir, opts)
.then(() => { /* done */ })
.catch((err) => { /* ooops */ })
// opts are directly passed to mkdirp
// see: https://www.npmjs.com/package/mkdirp