Added new scene event type: LOAD. Added dimension setter.

scene.go

@@ -7,6 +7,7 @@ type SceneEvent int64
 const (
 	NOOP      SceneEvent = 0
 	RESET     SceneEvent = 1 // reset to initial scene
+	LOAD      SceneEvent = 2
 	RELOAD    SceneEvent = 3 // reload current scene
 	COMPLETED SceneEvent = 4 // current scene has completed
 	ENDGAME   SceneEvent = 5 // shutdown all scenes
@@ -16,4 +17,5 @@ type Scene interface {
 	Update() error
 	Draw(screen *ebiten.Image)
 	SetEventHandler(e SceneEvent, f func())
+	SetDimensions(a Area)
 }