Music and better shooting indicators

Hello, everyone!

 So during the Chill Dev Winter Jam I got some feedback and one of the most important things that people wanted was music and a better way to know when they can throw a snowball so I added just that!

Added:

   Added Music and more sound effects

   Added a sound effect when a new snowball can be fired.

Changes:

   The rebuild boxes now disappear in a nicer way. The slowly fade into non-existence :)