Ted Dual Subtitles

Support dual subtitles for TED:
Language: Selecting 2nd subtitle language. It just supports 4 languages now.
1. It needs to generate dual subtitles locally and then load it to show dual subtitles.
2. It supports changing the subtitle font size.
3. it supports showing English subtitles on the website for study.

Notice:
1. The TED video need to support English subtitle.
2. It needs to enable subtitles for the video.
3. it translated online, it will take some time, If the video length more longer it takes more time. It supports download count when 0 means it is complete.
4. If you don't see "Download Count" mean not get the correct dada, please refresh the browser.