Improve code formatting and update to 2.0

The scripts were streamlined using more or less the following conventions:
 - space after a comma in lists of arguments
 - space around weak operators (+, -), no space around strong operators (*, /)
 - space after a comment start (#)
 - removed trailing spaces or tabs, apart from those that delimit the function indentation level (those could be removed too but since they are added automatically by the editor when typing code, keeping them for now)
 - function blocks separate by two newlines

The scene files were resaved with the (current) 2.0 format, and some scenes that were in XML format were converted to SCN, to be consistent across all demos.

misc/window_management/observer/observer.gd

@@ -1,16 +1,17 @@
 
 extends Spatial
 
+# member variables
 var r_pos = Vector2()
 var state
 
-const STATE_MENU=0
-const STATE_GRAB=1
+const STATE_MENU = 0
+const STATE_GRAB = 1
+
 
 func direction(vector):
-	var v = get_node("Camera").get_global_transform().basis * vector
+	var v = get_node("Camera").get_global_transform().basis*vector
 	v = v.normalized()
-	
 	return v
 
 
@@ -22,7 +23,6 @@ func impulse(event, action):
 
 
 func _fixed_process(delta):
-	
 	if(state != STATE_GRAB):
 		return
 	
@@ -34,31 +34,31 @@ func _fixed_process(delta):
 	var org = get_translation()
 	
 	if (Input.is_action_pressed("move_forward")):
-		dir += direction(Vector3(0,0,-1))
+		dir += direction(Vector3(0, 0, -1))
 	if (Input.is_action_pressed("move_backwards")):
-		dir += direction(Vector3(0,0,1))
+		dir += direction(Vector3(0, 0, 1))
 	if (Input.is_action_pressed("move_left")):
-		dir += direction(Vector3(-1,0,0))
+		dir += direction(Vector3(-1, 0, 0))
 	if (Input.is_action_pressed("move_right")):
-		dir += direction(Vector3(1,0,0))
+		dir += direction(Vector3(1, 0, 0))
 	
 	dir = dir.normalized()
 	
-	move(dir * 10 * delta)
-	var d = delta * 0.1
+	move(dir*10*delta)
+	var d = delta*0.1
 	
-	var yaw = get_transform().rotated(Vector3(0,1,0), d * r_pos.x)
+	var yaw = get_transform().rotated(Vector3(0, 1, 0), d*r_pos.x)
 	set_transform(yaw)
 	
 	var cam = get_node("Camera")
-	var pitch = cam.get_transform().rotated(Vector3(1,0,0), d * r_pos.y)
+	var pitch = cam.get_transform().rotated(Vector3(1, 0, 0), d*r_pos.y)
 	cam.set_transform(pitch)
 	
 	r_pos.x = 0.0
 	r_pos.y = 0.0
 
 
-func _input( event ):
+func _input(event):
 	if(event.type == InputEvent.MOUSE_MOTION):
 		r_pos = event.relative_pos
 	
@@ -76,4 +76,3 @@ func _ready():
 	set_process_input(true)
 	
 	state = STATE_MENU
-