Corrected error that is found during unit test

Author: Tasteful

src/Nest/Domain/Settings/CustomSimilaritySettings.cs

@@ -15,6 +15,8 @@ public CustomSimilaritySettings(string name, string type)
     {
       Name = name;
       Type = type;
+
+		SimilarityParameters = new Dictionary<string, object>();
     }
 
   }

src/Nest/Resolvers/ElasticContractResolver.cs

@@ -58,10 +58,10 @@ protected override JsonContract CreateContract(Type objectType)
 			if (objectType == typeof(IDictionary<string, AnalyzerBase>))
 				contract.Converter = new AnalyzerCollectionConverter();
 
-			if (objectType == typeof(IDictionary<string, TokenizerBase>))
+			if (objectType == typeof(IDictionary<string, TokenFilterBase>))
 				contract.Converter = new TokenFilterCollectionConverter();
 
-			if (objectType == typeof(MultiSearchResponse))
+			if (objectType == typeof(IDictionary<string, TokenizerBase>))
 				contract.Converter = new TokenizerCollectionConverter();
 
 			if (objectType == typeof(IDictionary<string, CharFilterBase>))