[fix] shallow clone the container options in case we pass in a intsan…

…tiated prototypal object

lib/winston/container.js

@@ -7,7 +7,8 @@
  */
 
 var common = require('./common'),
-    winston = require('../winston');
+    winston = require('../winston'),
+    extend = require('util')._extend;
 
 //
 // ### function Container (options)
@@ -36,9 +37,19 @@ var Container = exports.Container = function (options) {
 // an instance does not exist, one is created.
 //
 Container.prototype.get = Container.prototype.add = function (id, options) {
+  var existing;
   if (!this.loggers[id]) {
-    options = common.clone(options || this.options || this.default);
-    options.transports = options.transports || this.options.transports || [];
+    //
+    // Remark: Simple shallow clone for configuration options in case we pass in
+    // instantiated protoypal objects
+    //
+    options = extend({}, options || this.options || this.default);
+    existing = options.transports || this.options.transports;
+    //
+    // Remark: Make sure if we have an array of transports we slice it to make copies
+    // of those references.
+    //
+    options.transports = existing ? existing.slice() : [];
 
     if (options.transports.length === 0 && (!options || !options['console'])) {
       options.transports.push(this.default.transports[0]);