Wampy

- *breaking change*: replace `Client` init param `message_handler` with `message_handler_cls`
- removes a weird testing pattern from the early days where a `Router` instance was modelled inside the `Client`.
- fixes wampy run command not working
- fixes noisy teardowns
- fixes 100 , cannot send very long strings

- bumps Eventlet, Six, Pytest and Crossbar
- fixes 78 (expose call timeout to Client public API)
- fixes 67 (double slash in paths)
- fixes 88 (dependencies too strict)
- fixes 86 (WebSocket client->server pings)
- fixes GoodBye never received from the server
- fixes WebSocket tests accidentally fixed

- exposes test utils to other apps
- adds docs for flask integration

🐛 fix release
- fixes eventlet sleep `TypeError`

- fixes the forgotten `AppRunner` and adds test coverage
- adds `ticket` authentication
- Fixes RPC result args handling from Autobahn
- optional Eventlet for async networking

- adds support for the websocket CLOSE message