Add search by slug

[AMoo-Miki]

Allows searching by slug from site URL of series: https://www.thetvdb.com/series/$SLUG

[razzeee]

This should be send upstream first https://github.com/phate89/tvdbsimple

Anyway, we might have to fork at some point, as @phate89 hasn't been very active

[AMoo-Miki]

Would you like me to close this and raise a new one there?
I have a PR for metadata.tvdb.com.python, to be raised when this is merged, which depends on this to handle NFO parsing.

Or alternately, I could pull the functionality into metadata.tvdb.com.python and divorce tvdbsimple?

[razzeee]

I'm currently trying to figure out, if the xbmc org is open to act as the new upstream for tvdbsimple, please have some patience :)

[razzeee]

The other thing is, that the tvdb people are working on their own official scraper, so we're likely going to sunset the kodi official scraper anyway.