Add request to RedisPublisher to use SELF

The _wrap_user code that converts SELF to the active user needs the request instance. This can be passed through the RedisPublisher constructor.

```
def _wrap_users(users, request):
    ...
    for u in users:
        if u is SELF and request and request.user and request.user.is_authenticated():
            result.add(request.user.get_username())
    ....
```