Experimental Endurance HUD 0.31

- added km/l consumption
- most of the hud is working again
- saving/loading settings is disabled (for now)
- leaderboard only updates currently viewed vehicle

- added an experimental leaderboard feature
- settings and layout can now be saved
- fixed app showing in main menu and affecting ingame fonts

- all sections are now toggleable
- hide entire hud
- settings (work in progress)
- hud now shows name of car model on initial map load
- added pounds (car weight)
- fixed css affecting other apps