This allows procedures and event hooks to have more flexible signatures.
Along the lines of:
```python
@when(SomeEvent)
def hook(event):
...
@when(SomeOtherEvent)
def hook2():
...
```
Instead of supporting only the full context spec:
```python
@when(SomeEvent)
def hook(event, **ctx):
...
```
Closes: #400
The new configuration:
- Enables `backend.http` by default
- Removes the extra `config.auto.yaml` dependency
- Includes many more examples, lots of updates for existing examples,
and extensive comments.
The websocket service is no longer provided by a different service,
controlled by a different thread running on another port.
Instead, it's now exposed directly over Flask routes, using
WSGI+eventlet+simple_websocket.
Also, the SSL context options have been removed from `backend.http`, for
sake of simplicity. If you want to enable SSL, you can serve Platypush
through a reverse proxy like nginx.