LD build fixes

A few minor (all menu-related) fixes:

1. Fixed timer fail stopping you from selecting "retry"
2. Fixed infinite score accumulation of results menu and forgetting to reset score after using the "give up" option
3. Fixed minor title menu display issue after you give up
4. Fixed input (hopefully) for AZERTY users by using scan codes not key codes
5. Fixed a bug where first key press would be registered for keys you pressed before the game loaded, causing menus to skip.
6. Fixed continue showing up after you failed, and could not continue.
7. Added the LÖVE3D splash screen. Stop asking if it’s LÖVE. it’s still LÖVE!

No gameplay-related changes have been made. This should be the final update for the LD build.