Collate outputs in Kive

[donkirkby]

Currently, the Micall Watcher collates the output files, but that means that Kive won't recognize the checksums of those collated outputs. Kive should support pipelines with an arbitrary number of inputs, so write a pipeline to collate the files, and use it.

[CBeelen]

Currently, production Kive is at the latest tag v0.16.2. This tag does not include the code changes necessary to allow an arbitrary number of inputs. Those were made with this commit, as far as I can tell.
Test-kive is currently at a commit on the master branch, specifically this commit. This is ahead of the necessary changes to allow an arbitrary number of arguments.
So, to get this issue done, we first need to validate and deploy a new Kive version on production. We can start testing the collation on test-kive right away, though. Here's a useful example to follow for that.