code: function ready (fn) {
    if (isReady()) {
      return fn()
    } else if (document.addEventListener) {
      document.addEventListener('DOMContentLoaded', fn)
    } else {
      document.attachEvent('onreadystatechange', function () {
        if (isReady()) fn()
      })
    }
  }
docs: ready : ready(fn)
  Executes `fn` when the DOM is ready. If the DOM is already ready, the given
  callback will be called immediately.
  
  var ready = require('dom101/ready');
  
  ready(function () {
  ...
  });