gistfile1.scala

  lazy val dist = TaskKey[Unit](
    "dist", "Creates a project distribution in dist/ folder."
  )
  def distTask =
    dist <<=
      dist.dependsOn(compile, packageBin) <<=
      (update, crossTarget).map { case (updateReport, out) =>
        updateReport.allFiles.foreach { srcPath =>
          val destPath = out / "lib" / srcPath.getName
          IO.copyFile(srcPath, destPath, preserveLastModified=true)
        }
      }