New version 0.8.20

Hi everyone ! We've been developing a new offline mode called "campain", but it isn't ready yet !! But since we had a bug related to championships and how the ghosts are uploaded we're releasing this version. Anyway, championship scores weren't compromised by this bug, only the ghosts.

This is the changelog:

• Bugfix: Upload wrong ghost to LB
• More retries in server requests
• Lowered waiting time in end session GUIs
• Escape key (and corresponding joystick button) now goes back in the menu

We'll be releasing new cars, tracks and the new offline mode ASAP :)