title: Link gradle subproject to task
body: <p>This is how my project is set up </p>
  
  <pre><code>root
  - settings.gradle
  - build.gradle
  - subp1
  - subp2
  </code></pre>
  
  <p><em>settings.gradle:</em></p>
  
  <pre><code>rootProject.name = 'subs'
  include subp1, subp2
  </code></pre>
  
  <p><em>build.gradle:</em></p>
  
  <pre><code>....
  subprojects {
      repositories {
          jcenter()
          mavenCentral()
      }
  
      task dev(type: org.gradle.api.DefaultTask) //OK!
      task subdev(type: subp1.GenerateTask) //!!NOT OK!
  }
  </code></pre>
  
  <p><em>subp1/src/main/java/subp1/GenerateTask.java:</em></p>
  
  <pre><code>package subp1;
  
  import org.gradle.api.DefaultTask;
  import org.gradle.api.tasks.TaskAction;
  
  
  public class GenerateTask extends DefaultTask {
  
      @TaskAction
      public void generate() {
              System.out.println("subp1");
          }
  
  }
  </code></pre>
  
  <p>It looks like subp1.GenerateTask is not available when I am building the task in build.gradle.</p>
  
  <p>How do I let gradle know this task is available.</p>