sdbusplus：添加ObjectManager interface

ObjectManager接口可以一次性拿到对象及子对象的所有property，在交互中经常会用到。

sdbusplus提供了add_manager完成该接口的添加：

//server_obj.cpp
#include 
#include 
#include 
#include 
#include 
using namespace std;

int main()
{
    boost::asio::io_context io;
    auto conn = std::make_shared(io);
    conn->request_name("family.service");
    auto server = sdbusplus::asio::object_server(conn);
    server.add_manager("/home");
    shared_ptr iface = server.add_interface("/home/parent_obj","parent.data");
    iface->register_property("father", "Liming"s, sdbusplus::asio::PropertyPermission::readWrite);
    iface->register_property("mother", "Zhanghong"s, sdbusplus::asio::PropertyPerm