[nana] add 'nana' extractors (#2967)

docs/configuration.rst

@@ -1725,6 +1725,17 @@ Description
     Also emit metadata for text-only posts without media content.
 
 
+extractor.nana.favkey
+---------------------
+Type
+    ``string``
+Default
+    ``null``
+Description
+    Your `Nana Favorite Key <https://nana.my.id/tutorial>`__,
+    used to access your favorite archives.
+
+
 extractor.newgrounds.flash
 --------------------------
 Type

docs/gallery-dl.conf

@@ -189,6 +189,10 @@
             "format": "original",
             "include": "art"
         },
+        "nana":
+        {
+            "favkey": null
+        },
         "nijie":
         {
             "username": null,

docs/supportedsites.md

@@ -523,6 +523,12 @@ Consider all sites to be NSFW unless otherwise known.
     <td>Galleries</td>
     <td></td>
 </tr>
+<tr>
+    <td>Nana</td>
+    <td>https://nana.my.id/</td>
+    <td>Galleries, Favorites, Search Results</td>
+    <td></td>
+</tr>
 <tr>
     <td>Naver</td>
     <td>https://blog.naver.com/</td>