Boilerplate to add a new module

[Ethan McCue]

Hey all,

I'm doodling on JEP-198, and I was wondering if anyone had a line on the
boilerplate needed to add a new module to the build.

Just adding

src/
  java.json/
    share/
      classes/
        module-info.java
        java/
          json/
            Json.java
            ...

was enough to get it to show up under the output when I run "make images",
but I can't shake the feeling that I'm missing something.

(jtreg I assume has some extra setup? Anything else?)