Make 3DMaker Starter visible again

For some reason it was made invisible in 4e3e466a11e8c063cf64cc4426c19fa4a36276e3. It just works fine.

resources/definitions/maker_starter.def.json

@@ -4,6 +4,7 @@
     "name": "3DMaker Starter",
     "inherits": "fdmprinter",
     "metadata": {
+        "visible": true,
         "author": "tvlgiao",
         "manufacturer": "3DMaker",
         "category": "Other",