fix options priority (add to #315, thanks to @mickhansen)

lib/dao-factory.js

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