Don't set create flag for entries without user status

Setting the create-flag for entries without user status (read or watch
status) is useless.
Don't save anime/manga without read/watch status in DB

updateWithDetails() saved the anime/manga in the database even if the
entry had no read/watch status.
Merge pull request #164 from d-sko/unknown_entry_fix

Bugfix: prevent entries without status in anime/manga list