Add non-generic overload for As()

Relates #2408

Author: russcam

src/Nest/CommonAbstractions/LazyDocument/LazyDocument.cs

@@ -1,4 +1,5 @@
-using Newtonsoft.Json;
+using System;
+using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
 
 namespace Nest
@@ -7,22 +8,37 @@ namespace Nest
 	public interface ILazyDocument
 	{
 		/// <summary>
-		///
+		/// Creates an instance of <typeparamref name="T"/> from this
+		/// <see cref="ILazyDocument"/> instance
 		/// </summary>
-		/// <typeparam name="T"></typeparam>
-		/// <returns></returns>
+		/// <typeparam name="T">The type</typeparam>
 		T As<T>() where T : class;
+
+		/// <summary>
+		/// Creates an instance of <paramref name="objectType"/> from this
+		/// <see cref="ILazyDocument"/> instance
+		/// </summary>
+		/// <typeparam name="T">The type</typeparam>
+		object As(Type objectType);
 	}
 
 	public class LazyDocument : ILazyDocument
 	{
 		internal JToken _Value { get; set; }
 		internal JsonSerializer _Serializer { get; set; }
 
+		/// <inheritdoc />
 		public T As<T>() where T : class
 		{
 			var jToken = this._Value;
 			return jToken?.ToObject<T>(_Serializer);
 		}
+
+		/// <inheritdoc />
+		public object As(Type objectType)
+		{
+			var jToken = this._Value;
+			return jToken?.ToObject(objectType, _Serializer);
+		}
 	}
 }