Enums for TapNoteType, TapNoteSubType, and TapNoteSource

I intend to make additional useful information available on judgments,
such as TapNoteType and TapNoteSubType( for hold judgments ).

I am submitting this part as a separate pull request because it is more
generally applicable to anything TapNote related.

src/GhostArrowRow.h

@@ -25,8 +25,8 @@ protected:
 	const PlayerState* m_pPlayerState;
 
 	vector<Actor *> 	m_Ghost;
-	vector<TapNote::SubType> m_bHoldShowing;
-	vector<TapNote::SubType> m_bLastHoldShowing;
+	vector<TapNoteSubType> m_bHoldShowing;
+	vector<TapNoteSubType> m_bLastHoldShowing;
 };