fixes+changes:

- fixed windows build, using path, instead of path/filepath
- added switch + door, implemented relation (pair_system missing yet)
- fixed ldtk map loading, now using correct entitymap.png tileset

components/pairs.go

@@ -9,6 +9,7 @@ import (
 // manipulates the other
 type Bond struct {
 	ecs.Relation
+	Id, Ref string
 }
 
 // A door  has a relation  to a switch  using the Bond  component. The
@@ -19,6 +20,7 @@ type Door struct {
 	IsOpen      bool
 	OpenSprite  *ebiten.Image
 	CloseSprite *ebiten.Image
+	Id          string
 }
 
 func (door *Door) Open() *ebiten.Image {
@@ -35,4 +37,5 @@ type Switch struct {
 	IsOpen      bool
 	OpenSprite  *ebiten.Image
 	CloseSprite *ebiten.Image
+	Ref         string // the IId of the door
 }