anchor.diff:  The `type` attribute can be used to control for each field what concrete class the string value should be converted to.
   For example:
   
  -[source,java]
  +.Java
  +[source,java,role="primary"]
   ----
   class App {
       @Option(names = "--big", type = BigDecimal.class) // concrete Number subclass
  
positive.code: class Git : Runnable {
  
      @Option(names = ["--git-dir"], description = ["Set the path to the repository."])
      lateinit var gitDir : File
  }
  ----
  
  
negative.code: }
  ----
  
  .Kotlin
  [source,kotlin,role="secondary"]
  ----
  class App {
      @Option(names = ["--sqlType"], converter = [SqlTypeConverter::class])
      var sqlType = 0
  }
  ----
  
  Example implementation:
  
  .Java
  [source,java,role="primary"]
  ----
  class SqlTypeConverter implements ITypeConverter<Integer> {
      public Integer convert(String value) throws Exception {
  