Use already provided Kossel platform model

Added Pulley version of Kossel

resources/definitions/anycubic_kossel_linear.def.json

@@ -10,7 +10,7 @@
 		"preferred_variant_name": "0.4mm Nozzle",
 		"preferred_quality_type": "standard",
 		"preferred_material": "generic_pla",
-		"platform": "kossel_platform.stl",
+		"platform": "kossel_platform.3mf",
 		"machine_extruder_trains": {
 			"0": "anycubic_kossel_linear_extruder_0"
 		}

resources/definitions/anycubic_kossel_pulley.def.json

@@ -0,0 +1,16 @@
+{
+	"name": "Anycubic Kossel Pulley",
+	"version": 2,
+	"inherits": "anycubic_kossel_linear",
+	"metadata": {
+		"visible": true,
+		"machine_extruder_trains": {
+			"0": "anycubic_kossel_linear_extruder_0"
+		}
+	},
+	"overrides": {
+		"machine_name": {
+			"default_value": "Anicubic kossel Pulley"
+		}
+	}
+}