Agg metadata now serialized correctly on the request

Author: gmarz

src/Nest/Aggregations/Aggregation.cs

@@ -7,9 +7,6 @@ namespace Nest
 	public interface IAggregation 
 	{
 		string Name { get; set; }
-
-		[JsonConverter(typeof(VerbatimDictionaryKeysJsonConverter))]
-		[JsonProperty("meta")]
 		IDictionary<string, object> Meta { get; set; }
 	}
 

src/Nest/Aggregations/AggregationContainer.cs

@@ -50,6 +50,10 @@ public static implicit operator AggregationDictionary(AggregationBase aggregator
 	[JsonConverter(typeof(ReadAsTypeJsonConverter<AggregationContainer>))]
 	public interface IAggregationContainer
 	{
+		[JsonProperty("meta")]
+		[JsonConverter(typeof(VerbatimDictionaryKeysJsonConverter))]
+		IDictionary<string, object> Meta { get; set; }
+
 		[JsonProperty("avg")]
 		IAverageAggregation Average { get; set; }
 
@@ -178,6 +182,7 @@ public interface IAggregationContainer
 
 	public class AggregationContainer : IAggregationContainer
 	{
+		public IDictionary<string, object> Meta { get; set; }
 		public IAverageAggregation Average { get; set; }
 		public IValueCountAggregation ValueCount { get; set; }
 		public IMaxAggregation Max { get; set; }
@@ -273,6 +278,8 @@ public void Accept(IAggregationVisitor visitor)
 	public class AggregationContainerDescriptor<T> : DescriptorBase<AggregationContainerDescriptor<T>, IAggregationContainer>, IAggregationContainer
 		where T : class
 	{
+		IDictionary<string, object> IAggregationContainer.Meta { get; set; }
+
 		AggregationDictionary IAggregationContainer.Aggregations { get; set; }
 
 		IAverageAggregation IAggregationContainer.Average { get; set; }
@@ -527,9 +534,10 @@ Func<TAggregator, TAggregatorInterface> selector
 			where TAggregatorInterface : IAggregation
 		{
 			var aggregator = selector(new TAggregator());
-			
+
 			//create new isolated container for new aggregator and assign to the right property
-			var container = new AggregationContainer();
+			var container = new AggregationContainer() { Meta = aggregator.Meta };
+
 			assignToProperty(container, aggregator);
 
 			//create aggregations dictionary on `this` if it does not exist already