Extends the futures provided channels with
a metrics accessor.
Implements a metered variant of mpsc channels that provide an interface to extract metrics.
The following metrics are available:
- The amount of messages sent on a channel, in aggregate.
- The amount of messages received on a channel, in aggregate.
- How many times the caller blocked when sending messages on a channel.
- Time of flight in micro seconds (us)
Note: Currently there is no prioritization built in! It's on the agenda, but not quite there yet.