Add blank symbol and link-panel pages (#18)

src/main/resources/data/rivencraft/recipe/page.json

@@ -0,0 +1,13 @@
+{
+  "type": "minecraft:crafting_shapeless",
+  "category": "misc",
+  "ingredients": [
+    {
+      "item": "minecraft:paper"
+    }
+  ],
+  "result": {
+    "count": 1,
+    "id": "rivencraft:page"
+  }
+}