[splittiming] Write out the #SPEEDS tag.

We're not incrementing the version due to 0.70
being the main one with Split Timing.

If requested, maybe a version 0.64 or something.

src/NotesLoaderSSC.h

@@ -80,6 +80,7 @@ namespace SSCLoader
 	void ProcessWarps( TimingData &, const RString );
 	void ProcessLabels( TimingData &, const RString );
 	void ProcessCombos( TimingData &, const RString );
+	void ProcessSpeeds( TimingData &, const RString );
 }
 #endif
 /**