Migrate Sesame to RDF4J

[Alfiva]

Some time ago openrdf Sesame became Eclipse rdf4j. We have kept it for simplicity and because it just worked, but it is about time to migrate. A new branch has been created in context repo for this purpose.
In it, all context projects that used Sesame (CHe and related bundles) have been migrated to rdf4j dependencies. We must test that after the migration everything runs the same, not just compiling and testing (which it does) but also in runtime (so far seems to work OK).

Runtime in particular has required new dependencies for the RDF4J OSGI runtime bundle, which were solved with a custom mod of RDF4J's own OSGI bundling, making lots of "unnecessary" dependencies optional. This may lead to missing classes in some extreme cases if those are not included in OSGi, but I think the CHe capabilities can narrow down what is actually needed . This custom bundle is currently added to the context repo, but should be moved to uaal-3rd-party repo.

Other tangential things need to be updated too, like parent pom, Karaf features, wiki (when it's merged) and especially the CHe.properties file used in the itest runtime, because the default values have changed. And also check if there are other things inthis repo or others that use Sesame too.

[Alfiva]

Since we will have to rename the project sesame.uaal.store into rdf4j.uaal.store anyway, we could take the chance and rename it using the same template as the other projects, i.e. something like ctxt.rdf4j.store.
This project did not follow the ctxt.* template because it was not a bundle, just a jar lib to be used from ctxt.che.module.cardinality. But we could rename it now. What do you think?