Fix exporting playlist with an overly long name
Fix exporting playlist with an overly long name

The maximum length for the playlist name is 256 characters, but the
file names cannot be quite that long on ownCloud/Nextcloud. Hence, the
name is of the exported playlist is truncated to 240 characters at
maximum before it is used as name for the created file.

paulijar/music,owncloud/music,owncloud/music,paulijar/music,paulijar/music,owncloud/music,owncloud/music,paulijar/music,owncloud/music,paulijar/music