Add new beatmap genres and languages

osu.Game/Overlays/BeatmapListing/SearchGenre.cs

@@ -20,6 +20,10 @@ public enum SearchGenre
 
         [Description("Hip Hop")]
         HipHop = 9,
-        Electronic = 10
+        Electronic = 10,
+        Metal = 11,
+        Classical = 12,
+        Folk = 13,
+        Jazz = 14
     }
 }

osu.Game/Overlays/BeatmapListing/SearchLanguage.cs

@@ -11,7 +11,7 @@ public enum SearchLanguage
         [Order(0)]
         Any,
 
-        [Order(11)]
+        [Order(13)]
         Other,
 
         [Order(1)]
@@ -23,7 +23,7 @@ public enum SearchLanguage
         [Order(2)]
         Chinese,
 
-        [Order(10)]
+        [Order(12)]
         Instrumental,
 
         [Order(7)]
@@ -42,6 +42,12 @@ public enum SearchLanguage
         Spanish,
 
         [Order(5)]
-        Italian
+        Italian,
+
+        [Order(10)]
+        Russian,
+
+        [Order(11)]
+        Polish
     }
 }