ignore_above shoud be mapped as int not string on stringmapping ty @gmarz

Author: Mpdreamz

src/Nest/Domain/Mapping/Descriptors/StringMappingDescriptor.cs

@@ -88,7 +88,7 @@ public StringMappingDescriptor<T> Norms(NormsMapping normsMapping)
 			this._Mapping.Norms = normsMapping;
 			return this;
 		}
-		public StringMappingDescriptor<T> IgnoreAbove(string ignoreAbove)
+		public StringMappingDescriptor<T> IgnoreAbove(int? ignoreAbove)
 		{
 			this._Mapping.IgnoreAbove = ignoreAbove;
 			return this;

src/Nest/Domain/Mapping/Types/StringMapping.cs

@@ -56,7 +56,7 @@ public class StringMapping : IElasticType, IElasticCoreType
 		public string IndexAnalyzer { get; set; }
 
 		[JsonProperty("ignore_above")]
-		public string IgnoreAbove { get; set; }
+		public int? IgnoreAbove { get; set; }
 
 		[JsonProperty("search_analyzer")]
 		public string SearchAnalyzer { get; set; }