Small fixes and quality of life improvements

Small patch :
-Fixed a bug where the animation of the multiclic would still play after the mob death
-Now mob Hp does not fall bellow 0hp (no negative numbers shown)
-The last quests display the right amount of filling

-You can now adjust the sound of the game from everywhere in the game and the volume is retained when you close the game, option menu is cleaner

Little secret achievement has been added ;)