Docker command arguments

`ENDPOINT`, `GRAPH_STORE`, `ONTOLOGY` etc. `ENV` params would be better as image command arguments, e.g.

    docker run ... atomgraph/processor
      --endpoint="https://query.wikidata.org/bigdata/namespace/wdq/sparql"
      --graph-store="https://query.wikidata.org/bigdata/namespace/wdq/service"
      --ontology="https://github.com/AtomGraph/Processor/blob/develop/examples/wikidata#"