add beginnings of react and d3 challenges

under-construction/d3.json

@@ -0,0 +1,5 @@
+{
+  "name": "D3",
+  "order": 0.099,
+  "challenges": []
+}

under-construction/json-apis-and-ajax.json

@@ -1,6 +1,6 @@
 {
   "name": "JSON APIs and Ajax",
-  "order": 0.007,
+  "order": 0.0065,
   "challenges": [
     {
       "id": "bad87fed1348bd9aeca08826",
@@ -79,7 +79,6 @@
         "    }",
         "  ]",
         "",
-        "<code>  });</code>",
         "fcces",
         "",
         "<!-- You shouldn't need to modify code below this line -->",

under-construction/reactjs.json

@@ -0,0 +1,5 @@
+{
+  "name": "ReactJS",
+  "order": 0.099,
+  "challenges": []
+}