libsaria: Added comments

I'll be able to figure out these functions easier the next time I see
them.

libsaria/audio/progress.cpp

@@ -24,6 +24,7 @@ static bool get_position(gint64 &position)
 namespace libsaria
 {
 
+	/* Seek to this many seconds into the song */
 	void audio::seek_to(double pos)
 	{
 		gst_element_seek_simple(GST_ELEMENT(player),
@@ -32,7 +33,10 @@ namespace libsaria
 					pos);
 	}
 
-	/* Use to seek forward or backward in a song */
+	/*
+	 * Use to seek forward or backward in a song
+	 * by dt seconds.
+	 */
 	bool audio::seek(int dt)
 	{
 		bool ret;