Gets or sets a value indicating whether artifacts are extracted, flagged Artifact: content in a
marked-content sequence tagged Artifact, and on a tagged page read in Structure order,
content under an Artifact structure element or not in the structure tree at all. Default false:
artifacts (running heads, page numbers, decoration) are not part of the document's real content and are left out.
public bool IncludeArtifacts { get; set; }
ISO 32000-2 §14.8.2.2. In structure order, included artifacts under an Artifact element keep the element's place;
the others follow the structure's content, in content order.