Added base classes to encapsulate metadata in media

Aurora/Backend/Models/Media/AudioMetadata.cs

@@ -0,0 +1,35 @@
+using System;
+
+namespace Aurora.Backend.Models.Media
+{
+    public class AudioMetadata : BaseMetadata
+    {
+        public void AutioMetadata()
+        {
+        }
+
+        /// <summary>
+        /// The title of the song.
+        /// </summary>
+        /// <value></value>
+        public string Title { get; set; }
+
+        /// <summary>
+        /// The artist of the song.
+        /// </summary>
+        /// <value></value>
+        public string Artist { get; set; }
+
+        /// <summary>
+        /// The album from which the song belongs.
+        /// </summary>
+        /// <value></value>
+        public string Album { get; set; }
+
+        /// <summary>
+        /// The duration of the song.
+        /// </summary>
+        /// <value></value>
+        public string Duration { get; set; }
+    }
+}