code: function getFiles(dir, pattern, fn) {
  
    if ("function" === typeof pattern) {
      fn = pattern;
      pattern = undefined;
    }
  
    pattern = pattern || /.*/ig;
  
    fs.readdir(dir, function(err, files){
      if (err) return fn && fn(err);
  
      async.map(
        files,
        function(f, cb) {
          fs.stat(path.join(dir, f), function(err, stats){
            if (err) return cb && cb(err);
  
            cb && cb(null, { filename: f, stats: stats })  
          })
        },
        function(err, stats){
          if (err) return fn && fn(err);
  
          var fstats = stats.filter(function(f){
            return f.stats.isFile() && pattern.test(f.filename);
          });
  
          fn && fn(null, fstats);
      });
  
    });
  }
docs: Get files from the `dir` filtered with `pattern`
  
  @param {String} dir
  @param {Regex} pattern
  @param {requestCallback} fn callback