title: Converting Intellij Idea project to gradle project
body: <p>I have a Java Intellij Idea project that contains multiple modules 
  that I wish to convert to a gradle project. Is there a way to add gradle 
  to an existing project with multiple modules? I want to be able to use gradle to compile and generate JAR files (via artifacts) and generate JavaDocs using gradle. </p>
  
  <p>Intellij Idea version: Intellij Idea CE v2016.3.1<br>
  Gradle version: Gradle 3.2.1<br>
  Java version: 1.8.0_112<br>
  Javac version: 1.8.0_112<br></p>