Map Clearlogo images to cover type

(cherry picked from commit 809788eb2ed7e448f7f23101ae535533de57cd02)

src/NzbDrone.Core/MetadataSource/SkyHook/SkyHookProxy.cs

@@ -661,6 +661,8 @@ namespace NzbDrone.Core.MetadataSource.SkyHook
                     return MediaCoverTypes.Headshot;
                 case "fanart":
                     return MediaCoverTypes.Fanart;
+                case "clearlogo":
+                    return MediaCoverTypes.Clearlogo;
                 default:
                     return MediaCoverTypes.Unknown;
             }