provide better examples

[dvc94ch]

compiled all the tools pcap-analyzer test-analyzer etc. but not much happens when running them on a pcap file (other than displaying some simple stats about the pcap file itself).

Maybe something like this would be helpful to get started:

use anyhow::Result;
use libpcap_analyzer::{Analyzer, PluginRegistry};
use libpcap_analyzer::plugins::flows::FlowsInfo;
use libpcap_tools::{Config, PcapDataEngine, PcapEngine};
use std::fs::File;
use std::sync::{Arc, Mutex};

fn main() -> Result<()> {
    env_logger::init();
    let config = Config::default();
    let mut registry = PluginRegistry::new();
    let flows = Arc::new(Mutex::new(FlowsInfo::default()));
    registry.add_plugin(flows.clone());
    let analyzer = Analyzer::new(Arc::new(registry), &config);
    let mut engine = PcapDataEngine::new(analyzer, &config);
    let mut f = File::open("/home/dvc/ipld/quinn-noise-dissector/libp2p-quic.pcap")?;
    engine.run(&mut f)?;
    let json = flows.lock().unwrap().get_results_json();
    println!("{}", serde_json::to_string(&json)?);
    Ok(())
}