Module provides a decorator which wraps a generator in a Task
The Task iterates the generator until it ends and processes the yielded values.

Example:
```
@iq_request_task
request_something(self, jid):
    task = yield

    response = yield get_request_iq()
    result = process(response)

    if is_error_result(result):
        raise StanzaError(result)
    yield result
```