DemoService got the ipv6 ip when running under some network stack.

fixed issue #941, change `127.0.0.1` to '127.0.0.1'

* Update version to 2.5.8

* Update version to 2.5.8

* Add compatibility for Spring 3.2.x to resolve #17

* Add compatibility for Spring 3.2.x to resolve #17

* Add compatibility for Spring 3.2.x to resolve #17

* Add final to BEAN_NAME field

* Fixed #883

* Add @EnableDubboConfigBinding to fix #12

using default template

Refactor annotation config

NPE bug fixed.

Feature: support specify ip & port registered to registry from environment properties 

Optimize zookeeper block logic on app startup 

* 增加MethodValidated注解的测试用例  及对MethodValidated使用场景和用法的说明注释

* 将需要检查的分组维护到List<Class<?>> groups中，包括当前接口类及Default.class两个默认的分组

* 修改接口级别为jdk1.6; 按javadoc规范修改注释

 Adjust some config properties

Fixed #672: Monitor blocks when registry is unreachable (#777)

* Optimize(AbstractRegistry) registry cache, one registry file per 'registry & application', avoid reload (#685).

* Fixed #692 optimize zookeeper operation in service export/reference process: check already exists before create

Deprecate internal JSON impl and change to fastjson

The operator '+' has a higher operation priority than '?:'. A NPE will be thrown if getUrl() returns null, which is not expected.

fix the bug: cant enable override

合入hessian官方4.0.3部分源码，支持java.util.EnumSet反序列化