diffのカラーhtml,PDF作成
参考
https://qiita.com/him0net/items/1aa93e2f64104deab18f
http://news.mynavi.jp/column/osxhack/029/
https://qiita.com/DaisukeMiyamoto/items/0dccc753de9ae1d5cb4a#%E5%AF%BE%E5%BF%9C%E8%A8%80%E8%AA%9E
http://qune.cside.com/archives/000470.html