[c-nsp] script for finding unused switch ports

[lee.e.rian at census.gov]

Does anyone have a script for finding switch ports that haven't been used
in the last however many days that they're willing to share?

I threw something together using snmp & obvious problems are
- no error handling
- not handling sysUpTime wrapping around to zero
- not ignoring internal port-channels, vlans etc.

There's probably more stuff that I've missed, so I'm hoping someone else
has already figured out how to find (even better - find and shut down)
unused switch ports.

Thanks,
Lee