title: Creating a WriterT[F, W, A] from a Writer[W, A]
body: <p>In Scalaz, is there an easy way to convert an instance of <code>Writer[W, A]</code> (which is an alias for <code>WriterT[Id, W, A])</code> to <code>WriterT[F, W, A]</code>? </p>
  
  <p>I'm looking for something similar to the <code>optionT</code> function combined with <code>point</code>, but for writers instead:</p>
  
  <p>E.g.</p>
  
  <pre><code>// Similar situation, but using OptionT
  val opt:  Option[String] = Some("log")
  val optT: OptionT[IO, String] = optionT(opt.point[IO])
  
  // Case in hand, using WriterT
  val w:  Writer[String, Unit] = "log".tell
  val wt: WriterT[IO, String, Unit] = ???
  
  // Similar scenario
  val w:  Writer[String, Int] = 3.set("log")
  val wt: WriterT[IO, String, Int] = ???
  </code></pre>