Create a typedef for song ids

Passing around an inode number doesn't tell people what the inode is
used for.  Typedefing it to a song id is more helpful.

include/libsaria/track.h

@@ -4,6 +4,9 @@
 #include <libsaria/tags.h>
 #include <sys/types.h>
 
+/* Set up song id type */
+typedef ino_t sid_t;
+
 class Track
 {
 	private:
@@ -14,7 +17,7 @@ class Track
 		Track(TrackTag *);
 		~Track();
 
-		ino_t get_inode();
+		sid_t get_songid();
 		unsigned int get_track();
 		string get_title();
 		string get_lenstr();

libsaria/track.cpp

@@ -16,7 +16,7 @@ Track::~Track()
 {
 }
 
-ino_t Track::get_inode()
+sid_t Track::get_songid()
 {
 	if (tags)
 		return tags->get_inode();