Gripping: E_CMD_PENDING

[simonschmeisser]

I also see this warning after each grip:

Received command error code: E_CMD_PENDING

but I guess that is another issue?

Originally posted by @simonschmeisser in #16 (comment)

[simonschmeisser]

I think it tells us that the gripping is ongoing and that there will be another message when it's done. I haven't actually looked at the code if that is handled like this already. But we should either implement that or if done already reduce the noise