title: MetadataFileReference is inaccessible
body: <p>I recently updated my project to Roslyn 1.0, and can't find MetadataFileReference class anywhere.</p>
  
  <pre><code>references: new[] { new MetadataFileReference(typeof(object).Assembly.Location) }
  
  Error   CS0122  'MetadataFileReference' is inaccessible due to its protection level
  </code></pre>
  
  <p>What can I use instead?</p>