title: ViewImports to register tag helper not working
body: <p>I have created a Tag Helper in ASP.NET Core 2.0.</p>
  
  <p>It runs fine if I include the following line at the top of the page (.cshtml)</p>
  
  <pre><code>@addTagHelper *, DanLife
  </code></pre>
  
  <p>If I remove this line and place it into _ViewImports.cshtml the tag helper no longer works.</p>
  
  <pre><code>@using DanLife.TagHelpers
  @addTagHelper *, Microsoft.AspNetCore.Mvc.TagHelpers
  @addTagHelper *, DanLife
  </code></pre>
  
  <p>The assembly name is DanLife.</p>
  
  <p>The web application uses areas.</p>
  
  <p>I would like to know why my tag helpers are not registering for using in my views when registered in _ViewImports.cshtml.</p>