Change comments for examples_star_json build target

@gingerik, what do you think?
Did you mean to say "include" instead of "exclude"?

It is our own `build.js` task that handles the `src` property, passing the pattern to `closure-util` as "library files" (yes, I admit taking `src` and setting `lib` adds confusion - we can have a separate discussion about `lib` and `main` and decide if we want to expose the same in our build config syntax, but for now the `src` pattern becomes `lib`).  Library files are parsed for `goog.provide` and `goog.require`, dependencies are ordered, and the result is concatenated with any `js` files before calling the compiler.  So providing `js` files directly in a build config bypasses `closure-util`s dependency resolution step.