Struct representing a single OSM relation.

Example

%PBFParser.Data.Relation{
  id: 1843973,
  info: %PBFParser.Data.Info{
    changeset: 0,
    timestamp: #DateTime<2016-12-05 01:21:26.000Z>,
    uid: 0,
    user: "",
    version: 5,
    visible: true
  },
  members: [
    %PBFParser.Data.Member{id: 942351799, role: "admin_centre", type: :NODE},
    %PBFParser.Data.Member{id: 136822125, role: "outer", type: :WAY},
    %PBFParser.Data.Member{id: 136841179, role: "outer", type: :WAY},
    %PBFParser.Data.Member{id: 136841180, role: "outer", ...},
    %PBFParser.Data.Member{id: 136841188, ...},
    %PBFParser.Data.Member{...},
    ...
  ],
  tags: %{
    "addr:postcode" => "09220",
    "admin_level" => "8",
    "boundary" => "administrative",
    "name" => "Lercoul",
    "population" => "23",
    ...
  }
},