Sixth entry - Another Final release

v6  -- There are some hours left before the deadline so thought I'd do a little more

• Added volume control in pause menu. Changes are saved.
• Changed the sound effect for the single small coin
• Updated the controls that are shown on the floor to include P F and mouse buttons
• Created a new shop window that the user can show any time by pressing F. It'll now show lots of items. Hopefully that'll make it easier to upgrade.