401 fix.

Fix 403 for the third time.

Fix 403 again.

• Fix 403 for track streams. They tweaked their API a bit today.

• Fixed HTTP 400 error for some URL types. Ex: https://content.mora-qualitas.com/artist/Art.<artist ID>/album/alb.<album ID>
• Fixed fallback template for track filenames.
• Fixed padded track variable in config file.
• More code clean-up.

• Support for artist discographies, favourites, playlists and single tracks.
• Support for multiple text files via the -u arg (only the first one specified was processed before).
• Duplicate URL filter.
• Changed meta_language / -l option to ints.
• Code clean-up and refactor.

Android URL support.