[Database] Remove orphaned objects. Added helpers to access releases and artists

src/database/Release.hpp

@@ -29,8 +29,9 @@ namespace Database
 {
 
 class Track;
+class Release;
 
-class Release
+class Release : public Wt::Dbo::Dbo<Release>
 {
 	public:
 
@@ -64,6 +65,8 @@ class Release
 		std::string	getMBID() const		{ return _MBID; }
 		bool		isNone(void) const;
 		boost::posix_time::time_duration getDuration(void) const;
+		std::vector<Wt::Dbo::ptr<Artist> >	getArtists();	// Get the artists of this release
+		std::vector<Wt::Dbo::ptr<Track> >	getTracks();	// Get the tracks of this release
 
 		void setMBID(std::string mbid) { _MBID = mbid; }