Refactor Config class again
Save last know player_revision in a file, so we can use as fallback
Remove language checks, allow user to set any arbitrary value

This may seen strange, but Crunchyroll has lots of different languages
and it's impossible to support all of them. If the user knows what
it's doing it's possible to select any language available now.
Fix a mistake thinking ProxyHandler supported SOCKS5

But added an example on how to convert SOCKS5 requests to HTTP so we can
use it even with Tor.
Bump version