title: Where is HtmlEncode in Asp.NET 5
body: <p>I have a custom <code>IHtmlHelper</code> extension method that uses <code>TagBuilder</code> and returns an <code>HtmlString</code>.  I can no longer pass <code>tagBuiler.ToString()</code> to the <code>HtmlString</code> constructor as that just returns the typename now.  </p>
  
  <p>I see I can use the <code>tabBuiler.WriteTo(TextWriter, IHtmlEncoder)</code> method but I don't know exactly how to get my hands on an object that implments <code>IHtmlEncoder</code>.  I see encoders in both <code>System.Text.Encodings.Web</code> and <code>Microsoft.Framework.WebEncoders</code>.  But the types in the two namespace don't seem to play well together.</p>