Adds download buttons linking directly to available video files on Xtube. Adds a download button to Xtube and Pornhub.
Made downloaded file names match the video title and resolution. Needed because Xtube started serving all MP4 files with the same name. This workaround requires the use of a CORS proxy because the videos downloads are cross-origin. If you don't like downloading porn through one, you can still right click the download button and click "Save link as...".