Reorg tutorials to match nav, and update links

docs/tutorials/python/modular-tutorials/nfts/index.md

@@ -0,0 +1,15 @@
+---
+html: nfts-using-python.html
+parent: modular-tutorials-in-python.html
+top_nav_grouping: Article Types
+metadata:
+  indexPage: true
+seo:
+    description: Mint and sell NFTs on the XRP Ledger using Python.
+---
+# NFTs Using Python
+
+Mint and sell NFTs on the XRP Ledger using Python.
+
+
+{% child-pages /%}