Playlist support - generation and download of m3u playlist from a Plex playlist

[enchained]

On each playlist page you could add a button "Download playlist" that generates an m3u playlist (basically a list of local video urls in the specified order), downloads it in the browser - then users could open this exported playlist in a player of their choice. Such feature could be awesome.

I think it could be done via https://stackoverflow.com/questions/2951149/save-file-using-greasemonkey

[enchained]

I was able to implement the feature locally, although the code is very rough yet. Could do a pull request after I'll test it, maybe add some more formats.