title: Where are the docs for tasks.withType()?
body: <p>Gradle is a well documented project, but when I search for the docs for <code>tasks.withType()</code>, I only find the <a href="https://docs.gradle.org/2.3/javadoc/org/gradle/api/tasks/TaskCollection.html" rel="noreferrer">API docs</a>.</p>
  
  <p>Isn't this an official part of Gradle?</p>