code: function loadTemplates (dirs, options) {
      // require dirs to be array
      if (!Array.isArray(dirs)) {
          dirs = [dirs]
      }
      // templates indexed by absolute file name
      var templates = {}
      // load all templates in all directories
      return Promise.each(dirs, dir => {
          // load all files under dir
          return globby('**/*'+GLOBAL.ext, {
              cwd: dir,
              follow: true,
          })
          // compile templates for files
          .then(files => {
              return loadTemplatesFiles(dir, files, options, templates)
          })
      })
      // resolve with templates
      .then(() => templates)
  }
docs: @function loadTemplates
  
  @param {array|string} dirs
  
  @returns {Promise}