New: change types of various properties on Episode

- Id: string -> int (if not, catch exception when parsing xml)
- SeasonId: string -> int (idem Id)
- SeriesId: string -> int (idem Id)
- EpisodeNumber: int? -> int (always present)
- SeasonNumber: int? -> int (idem EpisodeNumber)
New: change type of property id on Show (string -> int)