Fix node#toJS by exposing a basic namespace map

It was using `ns` assuming it's available globally

src/index.js

@@ -15,6 +15,7 @@ var $rdf = {
   N3Parser: require('./n3parser'),
   NamedNode: require('./named-node'),
   Namespace: require('./namespace'),
+  ns: require('./ns'),
   Node: require('./node'),
   parse: require('./parse'),
   Query: require('./query').Query,

src/node.js

@@ -75,6 +75,7 @@ Node.fromValue = function fromValue (value) {
 }
 
 Node.toJS = function fromJS (term) {
+  const ns = require('./ns')
   if (term.elements) {
     return term.elements.map(Node.toJS) // Array node (not standard RDFJS)
   }

src/ns.js

@@ -0,0 +1,60 @@
+const Namespace = require('./namespace')
+
+const ns = {
+  adms: Namespace("http://www.w3.org/ns/adms#"),
+  as: Namespace("https://www.w3.org/ns/activitystreams#"),
+  bibo: Namespace("http://purl.org/ontology/bibo/"),
+  cc: Namespace("http://creativecommons.org/ns#"),
+  dbo: Namespace("http://dbpedia.org/ontology/"),
+  dbp: Namespace("http://dbpedia.org/property/"),
+  dbpedia: Namespace("http://dbpedia.org/resource/"),
+  dcat: Namespace("http://www.w3.org/ns/dcat#"),
+  dcterms: Namespace("http://purl.org/dc/terms/"),
+  dctype: Namespace("http://purl.org/dc/dcmitype/"),
+  dce: Namespace("http://purl.org/dc/elements/1.1/"),
+  doap: Namespace("http://usefulinc.com/ns/doap#"),
+  event: Namespace("http://purl.org/NET/c4dm/event.owl#"),
+  ex: Namespace("http://example.com/"),
+  exNS: Namespace("http://example.com/ns#"),
+  fhir: Namespace("http://hl7.org/fhir/"),
+  fhir3: Namespace("http://hl7.org/fhir/STU3"),
+  foaf: Namespace("http://xmlns.com/foaf/0.1/"),
+  geo: Namespace("http://www.w3.org/2003/01/geo/wgs84_pos#"),
+  gsp: Namespace("http://www.opengis.net/ont/geosparql#"),
+  gr: Namespace("http://purl.org/goodrelations/v1#"),
+  http: Namespace("http://www.w3.org/2011/http#"),
+  http07: Namespace("http://www.w3.org/2007/ont/http#"),
+  httph: Namespace("http://www.w3.org/2007/ont/httph#"),
+  hydra: Namespace("http://www.w3.org/ns/hydra/core#"),
+  ianalr: Namespace("http://www.w3.org/ns/iana/link-relations/relation#"),
+  ianamt: Namespace("http://www.w3.org/ns/iana/media-types/"),
+  link: Namespace("http://www.w3.org/2007/ont/link#"),
+  org: Namespace("http://www.w3.org/ns/org#"),
+  owl: Namespace("http://www.w3.org/2002/07/owl#"),
+  p: Namespace("http://www.wikidata.org/prop/"),
+  prov: Namespace("http://www.w3.org/ns/prov#"),
+  qb: Namespace("http://purl.org/linked-data/cube#"),
+  rdf: Namespace("http://www.w3.org/1999/02/22-rdf-syntax-ns#"),
+  rdfs: Namespace("http://www.w3.org/2000/01/rdf-schema#"),
+  schema: Namespace("http://schema.org/"),
+  sh: Namespace("http://www.w3.org/ns/shacl#"),
+  sioc: Namespace("http://rdfs.org/sioc/ns#"),
+  skos: Namespace("http://www.w3.org/2004/02/skos/core#"),
+  ssn: Namespace("http://www.w3.org/ns/ssn/"),
+  sosa: Namespace("http://www.w3.org/ns/sosa/"),
+  time: Namespace("http://www.w3.org/2006/time#"),
+  vann: Namespace("http://purl.org/vocab/vann/"),
+  vcard: Namespace("http://www.w3.org/2006/vcard/ns#"),
+  void: Namespace("http://rdfs.org/ns/void#"),
+  vs: Namespace("http://www.w3.org/2003/06/sw-vocab-status/ns#"),
+  wd: Namespace("http://www.wikidata.org/entity/"),
+  wdata: Namespace("https://www.wikidata.org/wiki/Special:EntityData/"),
+  wdref: Namespace("http://www.wikidata.org/reference/"),
+  wds: Namespace("http://www.wikidata.org/entity/statement/"),
+  wdt: Namespace("http://www.wikidata.org/prop/direct/"),
+  wdv: Namespace("http://www.wikidata.org/value/"),
+  xmlns: Namespace("http://www.w3.org/2000/xmlns/"),
+  xsd: Namespace("http://www.w3.org/2001/XMLSchema#"),
+}
+
+module.exports = ns