Refactoring Content/Media and ContentTypes/MediaTypes so the two are as close as possible. By doing this Media and Content are practically the same witht the except of a few properties.

This implements U4-10

src/Umbraco.Core/Models/IMedia.cs

@@ -2,6 +2,11 @@
 {
     public interface IMedia : IContentBase
     {
+        /// <summary>
+        /// Gets the ContentType used by this Media object
+        /// </summary>
+        IMediaType ContentType { get; }
+
         /// <summary>
         /// Changes the <see cref="IMediaType"/> for the current content object
         /// </summary>