Cleanup movies handling

Do not delete fields about a movie when we already have them
Movie has no UserID field

backend/models/episodes.go

@@ -68,18 +68,10 @@ func NewEpisodeFromDB(eDB *episodeDB) *polochon.ShowEpisode {
 // FillEpisodeFromDB fills a ShowEpisode from an episodeDB
 func FillEpisodeFromDB(eDB *episodeDB, pEpisode *polochon.ShowEpisode) {
 	// Keep the data that never changes but only if we have it
-	if eDB.TvdbID != 0 {
+	updateIfNonEmpty(&pEpisode.EpisodeImdbID, eDB.ImdbID)
-		pEpisode.TvdbID = eDB.TvdbID
+	updateIfNonEmpty(&pEpisode.ShowImdbID, eDB.ShowImdbID)
-	}
+	updateIfNonZeroInt(&pEpisode.TvdbID, eDB.TvdbID)
-	if eDB.ImdbID != "" {
+	updateIfNonZeroInt(&pEpisode.ShowTvdbID, eDB.ShowTvdbID)
-		pEpisode.EpisodeImdbID = eDB.ImdbID
-	}
-	if eDB.ShowImdbID != "" {
-		pEpisode.ShowImdbID = eDB.ShowImdbID
-	}
-	if eDB.ShowTvdbID != 0 {
-		pEpisode.ShowTvdbID = eDB.ShowTvdbID
-	}
 	pEpisode.Season = eDB.Season
 	pEpisode.Episode = eDB.Episode
 	pEpisode.Title = eDB.Title