Try fetching series from TMDb instead of OMDb

[JoosepAlviste]

Looks like there is more data there, and even a "discover" endpoint for showing popular series.

• https://www.themoviedb.org/
• https://developer.themoviedb.org/reference/intro/getting-started

TODOs:

• We need to give attribution: https://www.themoviedb.org/about/logos-attribution
• Default active season to 1, not the first season in the details view
• Ignore season 0 when calculating progress