Media: Extract isPresent flag from the sql request

This is mostly aiming at future proofness, in case we combine multiple
fetches in a single request. Having an unextracted column would cause it
to be extracted as the first column of the next entity.

src/Media.cpp

@@ -62,7 +62,8 @@ Media::Media( DBConnection dbConnection, sqlite::Row& row )
         >> m_insertionDate
         >> m_thumbnail
         >> m_title
-        >> m_isFavorite;
+        >> m_isFavorite
+        >> m_isPresent;
 }
 
 Media::Media( const std::string& title, Type type )

src/Media.h

@@ -121,6 +121,7 @@ private:
         std::string m_thumbnail;
         std::string m_title;
         bool m_isFavorite;
+        bool m_isPresent;
 
         // Auto fetched related properties
         mutable Cache<AlbumTrackPtr> m_albumTrack;