DynamicProxy method problem, like hashCode()

``` java
TestService service=RemotingServices.connect(uri, TestService.class);
service.hashCode();
```

as proxy, hashCode will call to remote, but user hope not

``` java
hashmap.put(service, uri);// hashmap.put perform service.hashCode as key
```

put() will hang util remoting timeout, and remote got error that NullPointerException as hashCode() method not found
