Inputs PF should provide rule specific information

Currently the PF input plugin only provides PF overall stats.

It would be great to have an option to also collect the output of 'pfctl -v -s rules' which are per rule statics.

(Example)
```
pass in log quick on vmx5 inet proto udp from to port = ntp keep state label "aaf67e315d4f23fcfd11353735e8a90b"
[ Evaluations: 14733 Packets: 148 Bytes: 11248 States: 0 ]
```
I would be good to collect the (label,Evaluations,Packets,Bytes,States) tuple.

The data enables monitoring of specific communications. In my specific use case I want to see whether specific IoT devices are up (have States>0), are continously interchanging data (Packet counter steadily increasing over time).

Start with the PF input plugin and its existing collection of overall PF statistics. Examine the output of `pfctl -v -s rules` and define collection of each rule's label, Evaluations, Packets, Bytes, and States; done means rule-specific metrics support monitoring those counters and state values.

Written by the indexing model from the issue text.