config.json in trackler-2.2.1.44

- old
+ new

@@ -1,11 +1,10 @@
 {
   "language": "Julia",
   "active": true,
   "blurb": "Julia is an open-source high-level, dynamic programming language whose sweet spot is technical and scientific computing. It is convenient for day-to-day work and fast enough for high performance computing.",
-  "exercises": [
-    {
+  "exercises": [{
       "uuid": "a668410d-41aa-4710-a68f-54521da6486d",
       "slug": "hello-world",
       "core": true,
       "unlocked_by": null,
       "difficulty": 1,
@@ -355,9 +354,19 @@
         "methods",
         "multiple dispatch",
         "function extension",
         "mathematics",
         "iterators"
+      ]
+    },
+    {
+      "uuid": "2ed6e171-04e1-b080-f383-a801b2564b3e0f4f1ee",
+      "slug": "grains",
+      "core": false,
+      "unlocked_by": "difference-of-squares",
+      "difficulty": 1,
+      "topics": [
+        "exceptions"
       ]
     }
   ],
   "foregone": [
 