Plugin for Webhooks

Hi everyone,

During one of the Sylius hackathons I’ve started working on, which allows you to define webhooks via admin panel on certain events. (Like you do on GitHub) I got it to a working state and it was pretty easy. That being said, it needs some testing, updated structure and documentation. If anyone is in need of such functionality - feel free to fork it/rename it. I’d be happy to help with some ideas and/or move the repository.