Dead code: Move Ordering.lean and Clock.lean

# Why?

This stuff is only needed for async, distributed streams.

# How?

- [ ] Move it into a separate repository, probably on my personal account so that in a couple of years when we're gonna be making `Conduit.lean` we won't forget this code exists.

Locate Ordering.lean and Clock.lean and review their references to confirm they are only needed for asynchronous, distributed streams. Then determine the separate repository destination and move the files there; the work is done when the code is removed from this repository and preserved in the new one.

Written by the indexing model from the issue text.