data: Don't identify episodes by their title when they have a guid

Rename episodes.rowid to id, replace the _pk title queries by a query that checks for guid first then falls back to title.

Closes #151 (closed) #204 (closed) #215 (closed) #216 (closed) #239 (closed) #317 (closed)

fixes some feeds that are currently not importing any episodes because of the primary key constraint failing during batch import. https://feeds.feedburner.com/streetfightradio for example would not import episodes without this patch.

Progress:

• test #151 (closed) (no rss)
• test #204 (closed) (found the rss in archive)
• test #215 (closed) can't get the feed from that date, it's not archived, no duplicates in latest version
• test #216 (closed) (has rss)
• test #239 (closed) (has rss)
• filter duplicate NewEpisodes out of this fn
• test batch import for https://feeds.feedburner.com/streetfightradio
• update old tests to check that no insert happened when an update is expected