def enrich_value(value)
      return enrich_node(value) if value.is_a?(ActiveTriples::Resource) &&
        value.node?
      return value if value.is_a?(DPLA::MAP::Controlled::Language)
      return nil if value.is_a?(ActiveTriples::Resource)
      enrich_literal(value)
    end
def enrich_value(value)
      return enrich_node(value) if value.is_a?(ActiveTriples::Resource) &&
        value.node?
      return value if value.is_a?(DPLA::MAP::Controlled::Language)
      return nil if value.is_a?(ActiveTriples::Resource)
      enrich_literal(value)
    end
Runs the enrichment against a node. Can match literal values, and Language
 values with a provided label.

 @example with a matching value
   lang = enrich_value('finnish')
   #=> #<DPLA::MAP::Controlled::Language:0x3f(default)>
   lang.providedLabel
   #=> ['finnish']
   lang.exactMatch.map(&:to_term)
   #=> [#<RDF::Vocabulary::Term:0x9b URI:http://lexvo.org/id/iso639-3/fin>]

 @example with no match
   lang = enrich_value('moomin')
   #=> #<DPLA::MAP::Controlled::Language:0x3f(default)>
   lang.providedLabel
   #=> ['moomin']
   lang.exactMatch
   #=> []

 @param value [ActiveTriples::Resource, #to_s]
 @return [DPLA::MAP::Controlled::Language, nil] a resource representing the
   language match.