Ｃ++中清理map的代码

　　正确做法是：

        if (pCameraConfigureMap != NULL)
        {
            std::map::iterator iter;
            for(iter = pCameraConfigureMap->begin(); iter != pCameraConfigureMap->end();)
            {
                delete iter->second;
                pCameraConfigureMap->erase(iter++);
            }
            //delete pCameraConfigureMap;
            pCameraConfigureMap = NULL;
        }