code: function getReleaseFile (names, cb) {
    var index = 0 // Lets keep track of which file we are on.
    /**
     * checkExists() is a first class function that we are using for recursion.
     */
    return function checkExists () {
      /**
       * Lets get the file metadata off the current file.
       */
      fs.stat(names[index], function (e, stat) {
        /**
         * Now we check if either the file didn't exist, or it is something
         * other than a file for some very very bizzar reason.
         */
        if (e || !stat.isFile()) {
          index++ // If it is not a file, we will check the next one!
          if (names.length <= index) { // Unless we are out of files.
            return cb(new Error('No unique release file found!')) // Then error.
          }
          return checkExists() // Re-call this function to check the next file.
        }
        cb(null, names[index]) // If we found a file, return it!
      })
    }
  }
docs: getReleaseFile() checks an array of filenames and returns the first one it
  finds on the filesystem.