add example JSON file with disabled/enabled items

Signed-off-by: Michael Leuschel <leuschel@uni-duesseldorf.de>

Button/button2.mch

@@ -3,6 +3,7 @@ MACHINE button2
 DEFINITIONS
      "LibraryMeta.def";
       VISB_JSON_FILE == "button2.json";
+      VISB_JSON_FILE1 == "button3.json";
       VISB_JSON_FILE2 == "button2_3d.json"
 VARIABLES
   button

Button/button3.json

+{
+  "svg": "button.svg",
+  "model": "button2.mch",
+  "model-name": "button2",
+  "comment": "uses new enabled/disabled feature in events",
+
+  "definitions": [
+     {"name":"width_TRUE",
+      "value": "1"
+     },
+     {"name":"width_FALSE",
+      "value": "2"
+     }
+  ],
+  "items": [
+    {
+      "id": "button_%0",
+      "attr": "visibility",
+      "value": "IF button=%0 THEN \"visible\" ELSE \"hidden\" END",
+      "repeat": [ "TRUE", "FALSE" ]
+    },
+    {
+      "repeat": [ "TRUE", "FALSE" ],
+      "for": {"from":"width_%0", "to":"width_%0"},
+      "comment": "just checking nested loops",
+      "id": "button_%0",
+      "attr": "stroke-width",
+      "value": "%1"
+    }
+  ],
+  "events": [
+    {
+      "id": "button",
+      "event": "press_button",
+      "hovers": [{ "attr":"stroke-width", "enter":"6", "leave":"1"}],
+      "items": [{"attr":"fill", "disabled":"\"green\"", "enabled":"\"red\""}]
+    },
+    {
+      "id": "buttonx",
+      "event": "release_button",
+      "hovers": [ { "attr":"opacity", "enter":"0.8", "leave":"1.0"}]
+    },
+    {
+      "id": "button_TRUE",
+      "event": "press_button",
+      "hovers": [{ "id":"hover_message",
+                    "attr":"text", "enter":"Button=TRUE", "leave":""},
+                 { "id":"root", "attr": "viewBox",
+                    "enter": "0 0 200 240" , 
+                    "leave": "0 150 200 240"}]
+    }
+  ]
+}