Removing PropertyValues-method from Content and Media and making it an extension method instead.

Adding the PropertyEditor model as internal to slowly adopt it using a slightly different model approach then in v5.
Minor refactoring of IEntity/Entity.

src/Umbraco.Core/Models/IContentBase.cs

@@ -74,12 +74,6 @@ namespace Umbraco.Core.Models
         /// <remarks>PropertyTypes are kind of lazy loaded as part of the object graph</remarks>
         IEnumerable<PropertyType> PropertyTypes { get; }
 
-        /// <summary>
-        /// Set property values by alias with an annonymous object
-        /// </summary>
-        [IgnoreDataMember]
-        object PropertyValues { set; }
-
         /// <summary>
         /// Indicates whether the content object has a property with the supplied alias
         /// </summary>