title: IntelliJ cannot resolve symbol in build.sbt
body: <p>IntelliJ IDEA 15 is reporting an unresolved symbol for my project definition in my <code>build.sbt</code> file</p>
  
  <pre><code>lazy val root = (project in file(".")).enablePlugins(PlayScala)
  </code></pre>
  
  <p>It's reporting an error with <code>project</code> and <code>in</code>.</p>
  
  <pre><code>Cannot resolve symbol project.
  Cannot resolve symbol in.
  </code></pre>
  
  <p>Everything else resolves perfectly and the project is otherwise all set up, sbt builds fine, activator runs fine.</p>