Fixes #50. Default function argument value is not supported in Node 4 and 5. Although this package no longer supports Node 4 or 5, this seems like a harmless update.

Author: richardgirges

lib/index.js

@@ -134,7 +134,7 @@ function processMultipart(options, req, res, next) {
         data: buf,
         encoding: encoding,
         mimetype: mime,
-        mv: function(path, callback = null) {
+        mv: function(path, callback) {
           // Callback is passed in, use the callback API
           if (callback) {
             doMove(