Document loading order of turtle files with references in-between them

[tobiasschweizer]

When loading data from turtle files into the triplestore with active consistency checking, the order in which the data is loaded matters if there are references in-between the data in the different files.

If A.ttl contains references defined in B.ttl, B.tll has to be loaded first.

Also consider loading order of ontologies: @benjamingeer suggests to load all the ontologies first.

[tobiasschweizer]

change the loading order in the scripts graphdb-knora-prod-data.expect and graphdb-knora-test-data.expect