title: How can I ensure that appsettings.dev.json gets copied to the output folder?
body: <p>I have three configuration files, one for each environment:</p>
  
  <ol>
  <li>appsettings.json -> production </li>
  <li>appsettings.dev.json -> development</li>
  <li>appsettings.stg.json -> staging</li>
  </ol>
  
  <p>If I set <em>ASPNETCORE_ENVIRONMENT</em> to <em>dev</em>, I get a runtime exception complaining about not being able to find appsettings.dev.json. I tried adding </p>
  
  <pre><code>"copyToOutput": [
    "appsettings.dev.json"
  ]
  </code></pre>
  
  <p>to the <code>buildOptions</code> section in project.json but it doesn't seem to have any effect. </p>
  
  <p>Is there another way I can force appsettings.dev.json to be copied to the output directory?</p>