code: function js2dtCLI (jsonFile, ramlTypeName) {
    const jsonData = fs.readFileSync(jsonFile).toString()
  
    if (ramlTypeName != null) {
      const raml = js2dt.js2dt(jsonData, ramlTypeName)
      return `#%RAML 1.0 Library\n${yaml.safeDump({ types: raml }, { 'noRefs': true })}`
    } else {
      const typeName = 'this__should__be__the__only__type'
      const raml = js2dt.js2dt(jsonData, typeName)
  
      const keys = Object.keys(raml)
      if (keys.length !== 1 || !keys.includes(typeName)) {
        throw new Error(`There is more than one type (${JSON.stringify(keys)}), please specify a name for the raml library`)
      }
  
      return `#%RAML 1.0 DataType\n${yaml.safeDump(raml[typeName], { 'noRefs': true })}`
    }
  }
docs: Just call js2dt.
  
  @param  {string} jsonFile
  @param  {string} ramlTypeName