Update #1 - BGM and General Fixes

Update #1

* Added background music.

* Fixed "Notes per Second" not advancing when in a different menu other than the main menu.

* Fixed the text in the main menu that displays the "Total Notes" and the "Notes per Second" overlapping onto the other buttons. 

*  Changed "Orchestra" to "Concerto" to match the music theme better. 

* Changed "Essence of Pyotr" to "Essence of Tchaikovsky". 

* Changed limit of "Harmonious Fragments" and the "Melodious Fragment" from 99 to 9999.