def entities(load = true, include_invalidated = false)
      activity_uris(include_invalidated) do |uri|
        agg = DPLA::MAP::Aggregation.new(uri)
        agg.get if load
        agg
      end
    end
def entities(load = true, include_invalidated = false)
      activity_uris(include_invalidated) do |uri|
        agg = DPLA::MAP::Aggregation.new(uri)
        agg.get if load
        agg
      end
    end
@param load [Boolean]  Whether to load the whole record from the LDP
   server.  DPLA::MAP::Aggregation#get is slow, because it results in a
   network request, so this provides the possibility of avoiding it.
   Default: true.

 @param include_invalidated [Boolean] Whether to include entities that
   have been invalidated with prov:invalidatedAtTime.  Default: false

 @see Krikri::EntityBehavior::entities
 @return [Enumerator] DPLA::MAP::Aggregation objects