I just stumbled across these classes recently and was looking for sample uses. No examples and other tests in the code base seem to use RequiredParameters and OptionType.
They also seem quite redundant with how ParameterTool itself works (tool.getRequired()). Should we drop them, in an attempt to reduce unnecessary code and confusion for users (multiple ways to do the same thing)? There are also many better command line parsing libraries out there, this seems like something we don't need to solve in Flink. Best, Stephan
