Description: Using ip_providers configured in qiang/config.py, batch-find-router will first get a list of ip to shoot at. For each ip, it invokes ./find-router destionation-ip to try to find GFW attached router on the path. The result is in var/gfw-attached-routers.csv. Description: find-router command will send packet to the destination-ip you specified, but the ttl will change from a very low value and increase one each time. When the packet reached the router with GFW attached, we will start to recieve "TCP RST" or "Wrong DNS Answer" due to GFW reactions. By doing this, we can tell if there is any GFW attached router between you and the destionation ip, and what's it ip address.