add data type properties of network metrics of characters to ontology

[ingoboerner]

API produces network-metrics for each character node in the play; the rdf-generation function will include them as well; they should be added to the ontology

map { "weightedDegree": 1.4e1, "degree": 9.0e0, "closeness": 5.333333333333333e-1, "eigenvector": 8.233954138362518e-2, "id": "bauern_4", "betweenness": 8.237293144208038e-4 }

[ingoboerner]

<dracon:degree xmlns:dracon="http://dracor.org/ontology#" rdf:datatype="http://www.w3.org/2001/XMLSchema#integer">28</dracon:degree>

<dracon:weightedDegree xmlns:dracon="http://dracor.org/ontology#" rdf:datatype="http://www.w3.org/2001/XMLSchema#integer">76</dracon:weightedDegree>

<dracon:closeness xmlns:dracon="http://dracor.org/ontology#" rdf:datatype="http://www.w3.org/2001/XMLSchema#decimal">0.7058823529411765</dracon:closeness>

<dracon:eigenvector xmlns:dracon="http://dracor.org/ontology#" rdf:datatype="http://www.w3.org/2001/XMLSchema#decimal">0.013230589825093965</dracon:eigenvector>

[ingoboerner]

betweenness!