[FROG] cumulusnetworks/frrouting image is missing /bin/ping

[Rafael Gozlan]

Hi Frogs!

I pulled the latest image from
https://hub.docker.com/r/cumulusnetworks/frrouting yesterday isn't
installed thus the ping command from vtysh is failing.

```
4a5446b1d048# ping ip 172.17.0.3
Can't execute ping: No such file or directory
```

I wanted to know if
https://github.com/FRRouting/frr/tree/master/docker/debian was the
associated dockerfile.

Thanks for any answer :)

-- 
raf