[ptp-dev] minor protocol change

[Greg Watson <g.watson@xxxxxxxxxxxx>]

Dave,

I've changed the protocol slightly so that there is an explicit event  
to indicate command failure (for submit/terminate job). I've added  
this to the pe and ll proxies. I also noticed that they weren't  
acknowledging a terminate job command correctly, so I've added that as  
well. Please take a look to make sure I've done it correctly.

Thanks,

Greg