Webhooks don't require SSL. We're going to publish a little Python script soon that can generate fake webhook notifications for local testing, but in the meantime, I'd suggest just using curl. Something like this:

curl http://127.0.0.1/whatever -d '{"deltas": {"users:" [12345]}}'

Another possibility is to use a tool like ngrok or localtunnel, which is what some of our beta testers did.