Initial support for GME's VGM/SPC playback and tag management.

Co-Authored-By: Jonas Kvinge <jonas@jkvinge.net>

src/core/song.h

@@ -106,6 +106,8 @@ class Song {
     FileType_S3M = 19,
     FileType_XM = 20,
     FileType_IT = 21,
+    FileType_SPC = 22,
+    FileType_VGM = 23, 
     FileType_CDDA = 90,
     FileType_Stream = 91,
   };