Represents the "IT" entry of the text markup annotation object.

It is an optional entry defined as part of the PDF 1.6 specification.

It contains a string representing a PDF name object.

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 179, page 403.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 182, page 489.