Recursive Extend Model Default Options for getterMethods and setterMethods

If I define default getters and setters and create a Modle with some getter / setters themselves, the default ones won't be added.

I think we should handle getters & setters the same way we handle classMethods & instanceMethods.

lib/sequelize.js

@@ -534,7 +534,7 @@ module.exports = (function() {
 
 
     if (globalOptions.define) {
     if (globalOptions.define) {
       options = Utils._.extend({}, globalOptions.define, options);
       options = Utils._.extend({}, globalOptions.define, options);
-      Utils._(['classMethods', 'instanceMethods']).each(function(key) {
+      Utils._(['classMethods', 'instanceMethods', 'getterMethods', 'setterMethods']).each(function(key) {
         if (globalOptions.define[key]) {
         if (globalOptions.define[key]) {
           options[key] = options[key] || {};
           options[key] = options[key] || {};
           Utils._.defaults(options[key], globalOptions.define[key]);
           Utils._.defaults(options[key], globalOptions.define[key]);