Moved the Amiibo nested model from the Library article in the DocC documentation catalog in the library target to its own Amiibo extension.

Sources/AmiiboService/Catalogs/AmiiboService.docc/Extensions/Amiibo.md

@@ -0,0 +1,10 @@
+# ``Amiibo``
+
+## Topics
+
+### Nested Models
+
+- ``Amiibo/Game``
+- ``Amiibo/Platform``
+- ``Amiibo/Release``
+- ``Amiibo/Usage``

Sources/AmiiboService/Catalogs/AmiiboService.docc/Library.md

@@ -61,10 +61,6 @@ $ make
 ### Models
 
 - ``Amiibo``
-- ``Amiibo/Game``
-- ``Amiibo/Platform``
-- ``Amiibo/Release``
-- ``Amiibo/Usage``
 - ``AmiiboSeries``
 - ``AmiiboType``
 - ``GameCharacter``