Code review comment for ~travisghansen/maas:master

Thanks for the patch! Couple of things

1. I think this should have an optional "id" field. This will allow one webhook service to handle multiple machines. For example if you create a wake on LAN webhook the id would be the MAC address.
2. We require unit tests for all branches to land.
3. MAAS uses Twisted[1] for HTTP calls. This allows MAAS to perform other tasks while waiting for the response.
4. See other comments below

If Twisted looks to complicated you can skip 2 and 3 and I'll Twistify it and add unit tests in a follow up branch.

[1] https://twistedmatrix.com/documents/current/web/howto/client.html