Update async library to 2.x

lib/logs.js

@@ -97,13 +97,21 @@ Logs.prototype.logFiles = function (callback) {
 
     async.filter(files, function (file, cb) {
       fs.stat(file.path, function (err, stat) {
+        if (err) {
+          return cb(err)
+        }
+
         file.created = stat.birthtime.toISOString()
         file.modified = stat.mtime.toISOString()
         file.formattedSize = filesize(stat.size)
         file.size = stat.size
-        cb(!err && stat.isFile())
+        cb(null, stat.isFile())
       })
-    }, function (files) {
+    }, function (err, files) {
+      if (err) {
+        return callback(err)
+      }
+
       files.sort(function (a, b) {
         return b.created.localeCompare(a.created) // Descending order
       })

package.json

@@ -19,7 +19,7 @@
   "dependencies": {
     "arma-class-parser": "^1.1.1",
     "arma-server": "0.0.10",
-    "async": "^0.9.0",
+    "async": "^2.6.4",
     "backbone": "1.3.3",
     "backbone.bootstrap-modal": "https://github.com/powmedia/backbone.bootstrap-modal/archive/632210077c2424be2ee6ea2aafe0d3fe016ae524.tar.gz",
     "backbone.marionette": "2.4.7",