This adds a new file processor mode. So the command changes from:
youtube-cue https://youtu.be/watch?v=dfjosufoadsi
to additionally supporting:
youtube-cue description.nfo
This however results in some problems. It is hard to get album and album
artist information from a plain text file, so we instead now have 2
additional flags:
--cue-performer "Performer for the entire track collection"
--cue-title "Title for the entire collection"
They usually, (but not always) will correspond to the album artist and
album title.
The changes are fairly obvious - I've also tried to make this more
modular, so hopefully this is easier to use as a module.
