title: Unresolved reference: LinearLayoutManager/RecyclerView
body: <p>I started building a movie database app using Kotlin based on a tutorial I found online (see <a href="https://medium.com/@juanchosaravia/keddit-part-3-extension-functions-android-extensions-and-more-faa7d232f232" rel="nofollow noreferrer">this link</a> for details.  While building the movie fragment file, I noticed an "unresolved reference:  LinearLayoutManager" and an "unresolved reference:  RecyclerView" error. 
   I have included the code below to and everything matches up like the tutorial except for those errors:</p>
  
  <pre><code>import android.os.Bundle
  import android.support.v4.app.Fragment
  import android.support.v7.widget.LinearLayoutManager
  import android.support.v7.widget.RecyclerView
  import android.view.LayoutInflater
  import android.view.View
  import android.view.ViewGroup
  import com.dburgnerjr.movietvshowdatabase.R
  import com.dburgnerjr.movietvshowdatabase.commons.inflate
  import kotlinx.android.synthetic.main.movie_fragment.*
  
  class MovieFragment : Fragment() {
  
      private val movieList by lazy {
          movie_list
      }
  
      override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?, savedInstanceState: Bundle?): View? {
          return container?.inflate(R.layout.movie_fragment)
      }
  
      override fun onActivityCreated(savedInstanceState: Bundle?) {
          super.onActivityCreated(savedInstanceState)
  
          movieList.setHasFixedSize(true)
          movieList.layoutManager = LinearLayoutManager(context)
      }
  }
  </code></pre>
  
  <p>Anything I overlooked?</p>