@spec parse(binary()) :: RtfDocument.t()

This function parses the given binary and returns a structured RTF document.

The structured RTF document is represented as a RtfDocument struct.

The RtfDocument contains a Header struct and a list of StyleBlock structs. A StyleBlock struct contains all information about the formatting of a specific block of text. It contains a Painter struct and a Paragraph struct. Lastly it contains the actual text of the block.