Ruby Changelog Parser. Should work with files like: http://svn.ruby-lang.org/repos/ruby/tags/v2_3_1/ChangeLog

ruby_changelog_parser.rb

require "vandamme"
require "github/markup"

header = /(\w+ \w+ \d+) (\d+:\d+:\d+ \d+)  (\w+ \w+  <.+>)/
changelog = File.read("ChangeLog.txt")
parser = Vandamme::Parser.new(changelog: changelog, version_header_exp: header, format: 'markdown')

File.open("ChangeLog.html", "w") do |f|
  GitHub::Markup.render('README.markdown', "* One\n* Two")
  f.write parser.to_html
end