Add support for other unsupported source types

pomice/enums.py

@@ -54,6 +54,8 @@ class TrackType(Enum):
     TrackType.HTTP defines that the track is from an HTTP source.
 
     TrackType.LOCAL defines that the track is from a local source.
+
+    TrackType.OTHER defines that the track is from an unknown source (possible from 3rd-party plugins).
     """
 
     # We don't have to define anything special for these, since these just serve as flags
@@ -63,6 +65,11 @@ class TrackType(Enum):
     APPLE_MUSIC = "apple_music"
     HTTP = "http"
     LOCAL = "local"
+    OTHER = 'other'
+
+    @classmethod
+    def _missing_(cls, value):
+        return cls.OTHER
 
     def __str__(self) -> str:
         return self.value