added sounds and music to menu/splash screen

Splash Screen.tscn

@@ -1,7 +1,8 @@
-[gd_scene load_steps=3 format=2]
+[gd_scene load_steps=4 format=2]
 
 [ext_resource path="res://Sprites/Splash_Screen.png" type="Texture" id=1]
 [ext_resource path="res://Splash Screen.gd" type="Script" id=2]
+[ext_resource path="res://Music/Interface/splash.wav" type="AudioStream" id=3]
 
 [node name="Splash Screen" type="Sprite"]
 self_modulate = Color( 1, 1, 1, 0 )
@@ -10,3 +11,8 @@ centered = false
 script = ExtResource( 2 )
 
 [node name="Tween" type="Tween" parent="."]
+
+[node name="BGM" type="AudioStreamPlayer" parent="."]
+stream = ExtResource( 3 )
+volume_db = -15.146
+autoplay = true