Now it properly "slideshows" just like the real client, instead of being
a static image like it was before. The banners are now clickable, but
there's still a bug causing the controls to be reloaded twice on startup
- delaying the first animation.
This is useful for users who choose to not use OTP, and the layout
is improved so the field is automatically hidden for Sapphire servers,
which don't support OTP.
The register button is also hidden automatically for Square Enix
accounts, instead of simply disabling the button.
