config.json in trackler-2.2.1.55

- old
+ new

@@ -537,10 +537,13 @@
       "slug": "matrix",
       "core": false,
       "unlocked_by": null,
       "difficulty": 1,
       "topics": [
-
+        "loops",
+        "type_conversion",
+        "integers",
+        "matrices"
       ]
     },
     {
       "uuid": "6434cc19-1ea3-43dd-9580-72267ec76b80",
       "slug": "rail-fence-cipher",