ProcessingInstruction interface represents a "processing instruction",
used in XML as a way to keep processor-specific information in the text of the document.
||The content of this processing instruction. This is from the first non white
space character after the target to the character immediately preceding the
||The target of this processing instruction. XML defines this as being the first token following the markup that begins the processing instruction.|
Copyright Lodovico Giaretta 2016 --