Is there an operator to connect an Observable to an Observer, and if not, which one would you prefer?

Hi Dag,

I think the pipe syntax for chaining operators is really cool, and am missing something similar to complete the chain.

That is, I find myself writing code like `xs = source | op.map( f1) | op.map( f2) | ...` and then having to complete it with a clunky

```
async def f():
subscription = await subscribe(xs, AnonymousAsyncObserver(sink_fun))
```

when I'd much rather just say something like

`f = xs > sink_fun`

where the > operator means we're coupling the source with an Observer that can consume it, returning a regular coroutine.

Is there something like that in aioreactive, and if not, do you have any immediate plans to write it?

If the answer to both of the above is 'no' , I'll have a go at writing one this week and would be grateful for any hints :)

Thanks a lot!