Integrate Pepper as loader

[chiarcos]

https://corpus-tools.org/pepper/knownModules.html

Ideally, this should be done via SALT XML, but cf. korpling/salt#140.
As an alternative, include Pepper via a Docker container.

[chiarcos]

In preparation, I created a non-interactive CLI for Pepper: https://github.com/acoli-repo/pepper-wrapper.
This can be used to produce PAULA data. A prototype for a PAULA reader is under https://github.com/acoli-repo/powla/tree/main/experimental/paula.

[chiarcos]

These two components are now bundled in a single Docker container (not Teanga-compliant): https://github.com/acoli-repo/powla/blob/main/experimental/salt/Dockerfile. This uses the bind protocol to access the file system directly, and writes its output to stdout, see sample call in https://github.com/acoli-repo/powla/blob/main/experimental/salt/.

Implementation recommendation: Develop a protocol for integrating Docker containers as Loaders and Writers into Fintan.

[chiarcos]

OpenAPI-compliant Docker now under https://github.com/acoli-repo/powla/tree/main/experimental/salt/swagger/python-server, Java client as prototype for integration with Fintan/CoNLL-RDF under https://github.com/acoli-repo/powla/blob/main/experimental/salt/swagger/java-client/Client.java. At the moment, this works for producing POWLA data, not CoNLL, yet. But POWLA can be seamlessly processed within Fintan.

[chiarcos]

@cfaeth : now would be a good point in time to take over ;)

[chiarcos]

working & presented at LREC ;)