make sure global options are not altered

lib/dao-factory.js

@@ -60,7 +60,7 @@ module.exports = (function() {
   }
   }
 
 
   DAOFactory.prototype.sync = function(options) {
   DAOFactory.prototype.sync = function(options) {
-    options = options ? Utils._.extend({}, this.options, options) : this.options
+    options = Utils._.extend({}, this.options, options || {})
 
 
     var self = this
     var self = this
     return new Utils.CustomEventEmitter(function(emitter) {
     return new Utils.CustomEventEmitter(function(emitter) {