New level, new menu and more!

Small update to the game :)

I added a new level which introduces the concept of moving platforms. I also updated the main menu and added the abillity to pause the game after feedback from user Viksy#2606 on Discord. 

I also added the abillity to reset your progress by clearing all the data (with a warning) as well as fixing a bug where the three first levels where unlocked from the beginning.