Prepare for automatic style sheet loading per page

This feature will be used in future development of the GUI
It allows pages to have their own style sheet settings stored in a related .css file

emhttp/plugins/dynamix/include/DefaultPageLayout.php

@@ -738,6 +738,10 @@ foreach ($pages as $page) {
   // create list of nchan scripts to be started
   if (isset($page['Nchan'])) nchan_merge($page['root'], $page['Nchan']);
   annotate($page['file']);
+  // include page specific stylesheet (if existing)
+  $css = "/{$page['root']}/styles/".strtolower($page['name']).".css";
+  if (is_file($docroot.$css)) echo '<link type="text/css" rel="stylesheet" href="',autov($css),'">',"\n";
+  // create page content
   empty($page['Markdown']) || $page['Markdown']=='true' ? eval('?>'.Markdown(parse_text($page['text']))) : eval('?>'.parse_text($page['text']));
   if ($close) echo "</div></div>";
 }