Fixed: Use Nzb title as scene name when available

- Use Nzb title as scene name when available
- Only use file name as scene name when its highly likely that it's an actual scene name
- Don't store `DRONE` as default release group in the DB
- Clean up the db removing obviously wrong scene names


if we have an Nzb name then we are good and we use that as scene name. this method is only used when there is no Nzb name available and we are trying to make a guess on if we should use file name or not.