message: Fix examples/buttons/index.html indentation
diff: <!DOCTYPE HTML>
  <html lang="en">
  -
  <head>
  <meta charset='UTF-8'>
  <title>solid-ui UI.widgets.buttons examples page</title>
  <pre id="viewSource-timestamp"></pre>
  <script>showSource('timestamp')</script>
  <div id="div-timestamp"></div>
  -
  </body>
  -
  </html>
  \ No newline at end of file
  