some update Less

Hello,

I add some update to Less,

1) the player has velocity when he walk now.
2) the jump is more organique (add rotation during jump).
3) some sound add (when click on interface button, or active object in game).
4) an intro screen before the main menu.
5) resolve the bug of loading image (It can be apear again, but really rare now).
6) a sprite was add for animation death player (but the respawn steel speed).

I hope you like it, I'm start thinking about the level two.