feature:support offline atomic command by lua

[cmgyqjj]

In the previous code, I noticed that there are some todos that need improvement. May I make some enhancements to the todo regarding the 'AccountServiceRedisImpl.offLine'?

@Override
public void offLine(Long userId) {

    // TODO: 2019-01-21 改为一个原子命令，以防数据一致性

    //删除路由
    redisTemplate.delete(ROUTE_PREFIX + userId);

    //删除登录状态
    userInfoCacheService.removeLoginStatus(userId);
}

As for the two instances of Redis deletion, I suggest using Lua scripts to execute them, to prevent the scenario where the route is deleted but the data remains inconsistent due to still being logged in.

[crossoverJie]

Could you please delete the unnecessary methods here?

cim/cim-forward-route/src/main/java/com/crossoverjie/cim/route/service/UserInfoCacheService.java

Line 36 in 05ffa2d

void removeLoginStatus(Long userId) ;