router-netsender: create netsender client that runs on pi for reporting router logs

We want as much insights into what is going on on the GL-MIFI routers so that when there is an issue we can more effectively diagnose it. A good start would be having access via the cloud to the router’s syslogs. It is proposed that a netsender client is written in go for a raspberry pi that will be connected to the router’s local network.