Writes the YAML file .rdoc_options to the current
directory containing the parsed options.
# File lib/rdoc/options.rb, line 1240
def write_options
RDoc.load_yaml
open '.rdoc_options', 'w' do |io|
io.set_encoding Encoding::UTF_8 if Object.const_defined? :Encoding
YAML.dump self, io
end
end