[hotfix] Don't return on gRPC errors in send, disable streams before closing
[hotfix] Don't return on gRPC errors in send, disable streams before closing

TheThingsNetwork/ttn,mgranberry/ttn,mgranberry/ttn,TheThingsNetwork/ttn,jvanmalder/ttn,mgranberry/ttn,jvanmalder/ttn,TheThingsNetwork/ttn,jvanmalder/ttn