Update announcements.json

announcements.json

 [
+        {"id":18,"title":"客户端出现bug 请暂时请用网页大厅登陆 my-card.in/rooms","url":"my-card.in/rooms","created_at":"2013-08-22T13:34:07+08:00","updated_at":"2013-08-22T07:12:08+08:00"},	
 	{"id":17,"title":"狮子男巫再次来袭！！","url":"http://forum.my-card.in/t/topic/153","created_at":"2013-08-20T13:34:07+08:00","updated_at":"2013-08-20T07:12:08+08:00"},	
 	{"id":14,"title":"论坛测试中~~~","url":"http://forum.my-card.in/","created_at":"2013-08-17T13:34:07+08:00","updated_at":"2013-08-17T07:12:08+08:00"},	
 	{"id":5,"title":"TCG805新卡等已更新，戳我查看新卡列表","url":"http://goo.gl/eoyaHv","created_at":"2013-08-17T13:34:07+08:00","updated_at":"2013-08-17T07:12:08+08:00"},