Add link to NETDUINO3_WIFI cmake-variants gist

docs/building/cmake-tools-cmake-variants.md

@@ -152,9 +152,17 @@ The following linkage section is a real example used to build nanoFramework for
 To make your life easier, we provide templates with pre-configured cmake-variants.json for the various reference targets. Just grab them from our Gist.
 
 -[ST_STM32F4_DISCOVERY](https://gist.github.com/nfbot/d4dbea239069146fe30d0869463507a8)
+
 -[ST_STM32F429I_DISCOVERY](https://gist.github.com/nfbot/06eadeca52fbed933b4b37a5942661a6)
+
 -[ST_NUCLEO_F091RC](https://gist.github.com/nfbot/cf7f6cfeb6f776ba068985bc44c005f0)
+
 -[ST_NUCLEO144_F746ZG](https://gist.github.com/nfbot/6de229c9e6e64d5c48b729e077af7153)
+
 -[ST_STM32F769I_DISCOVERY](https://gist.github.com/nfbot/efd47b5cfffdc7e54e388c37f1cb7a9c)
+
 -[MBN_QUAIL](https://gist.github.com/nfbot/06723075c41d4e8f66ba511a4ce46e3f)
+
+-[NETDUINO3_WIFI](https://gist.github.com/nfbot/dae2411ba9d2251c45d302ea1cac135a)
+
 -[ESP32](https://gist.github.com/nfbot/627051a2f9f459d3c8f17752ca4985be)