Add the Kumyk language

This is being used in the Wikimedia Incubator,
and must be available in translatewiki and elsewhere.

data/langdb.yaml

@@ -286,6 +286,7 @@ languages:
   ku: [ku-latn]
   ku-arab: [Arab, [EU, ME], كوردي]
   ku-latn: [Latn, [EU, ME], Kurdî]
+  kum: [Cyrl, [EU], къумукъ]
   kv: [Cyrl, [EU], коми]
   kw: [Latn, [EU], kernowek]
   ky: [Cyrl, [AS], Кыргызча]

language-data.json

@@ -1798,6 +1798,13 @@
             ],
             "Kurdî"
         ],
+        "kum": [
+            "Cyrl",
+            [
+                "EU"
+            ],
+            "къумукъ"
+        ],
         "kv": [
             "Cyrl",
             [
@@ -5081,6 +5088,7 @@
             "kbd",
             "myv",
             "mdf",
+            "kum",
             "kv",
             "lez",
             "krc",