default InjectBundle withBundle(InjectBundle next) {
        requireNonNull(next);
        return () -> Stream.concat(injectables(), next.injectables());
    }
Creates and returns a new InjectBundle that contains the classes
in this InjectBundle plus the classes in the given {@code next} InjectBundle.

@return a new InjectBundle that contains the classes
        in this InjectBundle plus the classes in the given {@code next} InjectBundle
@throws NullPointerException if the provided {@code next} is {@code null}
common-parent/injector/src/main/java/com/speedment/common/injector/InjectBundle.java