Pawl WebSocket Client
Related to #14.
This PR replaces devristo/phpws with ratchet/pawl, a WebSocket client that's more closely aligned with the rest of the ReactPHP ecosystem.
PHP7 is already supported, though some older versions have bugs. This is due to a workaround in react/socket-client for handling encrypted streams. I'll save you the trip down the rabbit hole: Some versions work, some don't, and the problem is the openssl extension. Depending on your PHP version, you might need to pin react/socket-client to a specific release if things aren't working quite right.
PS: I added the examplebot and the robo task primarily for testing. If you're interested in merging this, but would rather not include those changes, I would be happy to remove them.
This is definitely a good solution for the time being. Nice job! :+1:
I still plan on doing a rewrite in the future with Icicle, but it may be some time yet before the Icicle websocket package is ready.