Add a switch button for sukebei

[akuma06]

Implementing Sukebei to the app is not that hard, we only have to change the api base url to sukebei.pantsu.cat/api .
User account is shared between both website and the token is the same, so we don't have to touch on user object.

Need to be changed

• Recently played list should depend on the website chosen (sukebei or nyaa) since the torrents id would conflict with each other.
• API base url
  Everything else can be left untouched.

Further improvements possible

With the theming support of the app #8, we could when sukebei is selected apply a more pinkish, redish, blackish theme.