add cli support

[ShaneDean]

hi @devlauer ,

I want to use the plantuml-generator in orther language, so I wrapper it into a cli.

java -jar plantuml-generator-cli.jar [class/sequence] [options]

I am interested in this program, please let me know if there is anything I might be able to help with.

[devlauer]

Sorry for the late reply. Unfortunately, I'm only now getting around to looking at your merge request. It looks pretty good so far. Thank you for this code contribution.

However, I still have one question: What is the Lombok problem in todo.md all about? To me it looks like a LombokProcessor problem in relation to the module path in java, because it uses an internal class (JavacProcessingEnvironment) of the module jdk.compiler. I don't see any reference to your CLI module here. I would therefore ask you to remove the todo.md or solve the problem so that I can adopt the code without issues.

I have also noticed that there is no documentation (based on Antora) for the new module. Could you add this? Then I could merge your request and make it available as a new version. Thank you in advance!

[ShaneDean]

@devlauer
Sorry it took so long to get the rest of the work done.