add nfc-tags page

Author: benhansen-io

docs/nfc-tags.mdx

@@ -0,0 +1,11 @@
+---
+id: nfc-tags
+title: NFC Tags
+---
+Boppo is compatible with some off the shelf NFC tags when [Developer Mode](developer-mode) is enabled.
+
+You can write commands such as a "start wasm user/wasm/your_activity.wasm" to make bookmarks for particular activites.
+
+The NFC antenna is located at the center of [buttons 1, 2, 6, and 7](button-layout).
+
+The tags should be 25mm or smaller. Larger credit card style tags do not work.