docs: function initHandlebarsHelpers (config) {
      // load handlebars-helpers helper library if flag set
      if (config.handlebarsHelpers) {
          config.handlebars.helpers = handlebarsHelpers()
      }
      // get helpers dir
      var helpersDirs = config.dir.helpers
      // load files from each helpers dir
      _.each(helpersDirs, helpersDir => {
          // get directory listing
          try {
              var files = fs.readdirSync(helpersDir)
          }
          // ignore errors
          catch (err) {
              debug('init helpers readdir:', err)
          }
          // load any js files
          _.each(files, file => {
              // get relative path
              var relPath = path.relative(__dirname, helpersDir)
              // add relative path to file for require
              file = `./${relPath}/${file}`
              // skip file if it does not have js extension
              if (!file.match(/\.js$/)) {
                  debug('init helpers: skipping file %s', file)
                  return
              }
              debug('init helpers: require %s/%s', __dirname, file)
              // require abs version of file - this will throw error
              var module = require(file)
              // iterate over module and add any functions to helpers
              _.each(module, (func, name) => {
                  // add helper if function
                  if (typeof func == 'function') {
                      debug('init helpers: added helper %s', name)
                      // add helper
                      config.handlebars.helpers[name] = func
                  }
                  // skip if not a function
                  else {
                      debug('init helpers: skipping %s - not a function', name)
                  }
              })
          })
      })
  }