Document the Jelly-Patch-related modules

[Ostrzyciel]

Here: https://jelly-rdf.github.io/jelly-jvm/dev/

There is no mention of core-patch or anything else related with Jelly-Patch. We need to list it on the main page like the other packages, and add at least a basic guide explaining how to work with it.

[Ostrzyciel]

Would be good to document using it (first and foremost) with jena-patch, as Jena has a full RDF Patch implementation.

We can also document the low-level API.