Added RichMediaAnnotation class: Represents a rich media annotation.
Added RichMediaAnnotationActivation class: Specifies the activation conditions of a RichMediaAnnotation.
Added RichMediaAnnotationDeactivation class: Specifies the deactivation conditions of a RichMediaAnnotation.
Added RichMediaAnnotationPresentationStyle class: Defines possible values for RichMediaAnnotation.PresentationStyle.
Added RichMediaAnnotationContentType enumeration: Defines possible types of RichMediaAnnotation content.
Added GcPdfDocument.RemoveDuplicateImages method: Removes images with identical content from the current document.
Added MergeDocumentOptions.RemoveDuplicateImages property: Gets or sets a value indicating whether to remove duplicate images after merging.
Added GcGraphics.DrawRotatedText() method: Draws rotated text inside an unrotated rectangle (similar to how MS Excel draws rotated text in borderless cells).
Added GcGraphics.DrawSlantedText() method: Draws rotated text inside a slanted rectangle (similar to how MS Excel draws rotated text in cells with borders).
Added GcGraphics.MeasureRotatedText() method: Calculates the bounds of rotated text inside an unrotated rectangle.
Added GcPdfDocument.GetImages method overload that allows including unreferenced images (by default, they are not included).
Fixed null reference exception occurs when merging a certain PDF with other PDFs.
Fixed exception that occurs when saving a certain PDF as an image.
