Update README.md (#135)

Author: SleepWellPupper

README.md

@@ -9,3 +9,5 @@ The [JsonSchemaGenerator](JsonSchemaGenerator) generator generates json schemata
 The [UtilityGenerators](UtilityGenerators) generator helps you write code generators and analyzers.
 
 The [CopyTo](CopyTo) generator generates methods to copy the contents of one instance to another. I created this generator for a friend, so it is not as feature rich as it could be.
+
+The [VisitorGenerator](VisitorGenerator) generator generates visitor pattern implementations for various node kinds, for example for implementing syntax tree walkers.