class Asciidoctor::Extensions::DocinfoProcessor

to add content to the header.
If a location is not specified, the DocinfoProcessor is assumed
DocinfoProcessors implementations must extend DocinfoProcessor.
The placement of docinfo content is controlled by the converter.
the header and/or footer of the generated document.
Public: DocinfoProcessors are used to add additional content to

def initialize config = {} 

def initialize config = {}
  super config
  @config[:location] ||= :head
end

def process document 

def process document
  raise ::NotImplementedError, %(#{DocinfoProcessor} subclass #{self.class} must implement the ##{__method__} method)
end