title: Add-Migration command not working in EF 7 for UWP app
body: <p>I'm following <a href="http://ef.readthedocs.org/en/latest/getting-started/uwp.html" rel="nofollow">getting started with EF 7 for UWP apps</a> official tutorial.</p>
  
  <p>When I'm at Add-Migration MyFirstMigration, it throws following error:</p>
  
  <pre><code>PM&gt; Add-Migration MyFirstMigration
  
  Add-Migration : Exception calling "CreateInstanceAndUnwrap" with "8" argument(s): "Could not load file or assembly 'AppShellProject, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' 
  or one of its dependencies. An attempt was made to load a program with an incorrect format."
  At line:1 char:1
  + Add-Migration MyFirstMigration
  + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      + CategoryInfo          : NotSpecified: (:) [Add-Migration], MethodInvocationException
      + FullyQualifiedErrorId : BadImageFormatException,Add-Migration
  </code></pre>
  
  <p>Has anyone figured out any workaround?</p>