unnormalize

# File lib/rexml/text.rb, line 310
    def Text::unnormalize( string, doctype=nil, filter=nil, illegal=nil )
      rv = string.clone
      rv.gsub!( /\r\n?/, "\n" )
      matches = rv.scan( REFERENCE )
      return rv if matches.size == 0
      rv.gsub!( NUMERICENTITY ) {|m|
        m=$1
        m = "0#{m}" if m[0] == ?x
        [Integer(m)].pack('U*')
      }
      matches.collect!{|x|x[0]}.compact!
      if matches.size > 0
        if doctype
          matches.each do |entity_reference|
            unless filter and filter.include?(entity_reference)
              entity_value = doctype.entity( entity_reference )
              re = /&#{entity_reference};/
              rv.gsub!( re, entity_value ) if entity_value
            end
          end
        else
          matches.each do |entity_reference|
            unless filter and filter.include?(entity_reference)
              entity_value = DocType::DEFAULT_ENTITIES[ entity_reference ]
              re = /&#{entity_reference};/
              rv.gsub!( re, entity_value.value ) if entity_value
            end
          end
        end
        rv.gsub!( /&/, '&' )
      end
      rv
    end