don't use special special sort episode/season members as episode/season number
fixes #14281
[confluence] update episode/season labels to better handle empty season infolabel
don't depend on special sort epsiode/season when formatting label and update season/episode format to be more in line with values returned by infomanager
Merge pull request #2693 from pieh/special_episodes

Special episodes infolabels cleanup, closes #14281