Better querying of the evaluations results

[vemonet]

Users should be able to query the evaluations results to answer questions like "get me all evaluations that have a score of 1 for the metric test i1-structrured metadata and a score of 0 for i1-license"

Either:

• add functions to graphql, cf. https://dgraph.io/docs/graphql/schema/search/
• Or load the whole DB in a triplestore for SPARQL querying

[vemonet]

Done

query MyQuery {
  evaluations(filterTests: [
    {metric: "https://w3id.org/fair-enough/metrics/tests/f1-metadata-identifier-persistent", score: 1},
    {metric: "https://w3id.org/fair-enough/metrics/tests/f3-metadata-identifier-in-metadata", score: 1}
  ]) {
    subject
    results {
      metricTest
      score
    }
  }
}