Fix #1821 AutoMap on PutMappingDescriptor ignored maxRecursion

Author: gmarz

src/Nest/Indices/MappingManagement/PutMapping/PutMappingRequest.cs

@@ -138,7 +138,7 @@ public PutMappingDescriptor(IndexName index, TypeName type) : base(r=>r.Required
 		public PutMappingDescriptor<T> AutoMap(IPropertyVisitor visitor = null, int maxRecursion = 0) => Assign(a =>
 		{
 			a.Properties = a.Properties ?? new Properties();
-			var autoProperties = new PropertyWalker(typeof(T), visitor).GetProperties();
+			var autoProperties = new PropertyWalker(typeof(T), visitor, maxRecursion).GetProperties();
 			foreach (var autoProperty in (IEnumerable<KeyValuePair<PropertyName, IProperty>>)autoProperties)
 				a.Properties[autoProperty.Key] = autoProperty.Value;
 		});

src/Nest/Mapping/Visitor/PropertyWalker.cs

@@ -12,7 +12,7 @@ public class PropertyWalker
 		private readonly int _maxRecursion;
 		private readonly ConcurrentDictionary<Type, int> _seenTypes;
 
-		public PropertyWalker(Type type, IPropertyVisitor visitor, int maxRecursion = 0)
+		public PropertyWalker(Type type, IPropertyVisitor visitor, int maxRecursion)
 		{
 			_type = GetUnderlyingType(type);
 			_visitor = visitor ?? new NoopPropertyVisitor();