Use compound splitter release

[oktaal]

          I've FAIR-ed up the compound splitter recently, so you could also download the distribution from `https://github.com/UUDigitalHumanitieslab/compound-splitter/releases/download/0.0.0/compound-splitters-nl-0.0.0.tar.gz` and then just pip install the zipped file.

Originally posted by @lukavdplas in #75 (comment)

[oktaal]

This doesn't work yet: https://github.com/UUDigitalHumanitieslab/tscan/tree/feature/compound-splitter-release