title: Javadoc ignoring subpackages
body: <p>I've got a project with four modules, with two of them being implementation, one being API interfaces, and one parent module with the entry-point, so I'm trying to only include the parent module and the entry-point. I use the following method:</p>
  <pre><code>task genJavadocs(type: Javadoc) {
      options.source = &quot;8&quot;
      options.addStringOption(&quot;link&quot;, &quot;https://docs.oracle.com/javase/8/docs/api/&quot;)
      Project[] projects = [project(':core'), project]
      source projects.collect { project -&gt; project.delombok }
      classpath = files(projects.collect { project -&gt; project.sourceSets.main.compileClasspath })
  }
  
  javadoc {
      dependsOn delombok
      source = delombok
      failOnError = false
  }
  
  task javadocJar(type: Jar, dependsOn: build) {
      from genJavadocs
      archiveClassifier.set('javadoc')
  }
  
  build.finalizedBy(javadocJar)
  </code></pre>
  <p>This generates javadocs for both modules, with the javadocs folder having HTML files for classes in both modules, however overview only shows classes from the core project. This is how it looks:</p>
  <pre><code>\- mypackage
  \ - mypackage.api
    \ - mypackage.api.APIClasses.java
  \ - mypackage.EntryPoint.java
  </code></pre>
  <p>With the folder containing EntryPoint.html, Overview contains mypackage.api, but no mypackage in Overview.</p>
  <p>How can I get the generated Javadoc Overview to include mypackage, not just mypackage.api?</p>