/**
  * Renders HTML from template
  *
  * @param array $customVariables
  */
 private function renderHTML($customVariables = array())
 {
     $twig = new \Twig_Environment(new \Twig_Loader_Filesystem(self::TEMPLATES_DIRECTORY));
     $customPageTitle = $this->config->getMapPageTitle();
     $pageTitle = array('GeoPal');
     if (!empty($customPageTitle)) {
         array_unshift($pageTitle, $customPageTitle);
     }
     $this->mapPageHTML = $twig->loadTemplate(self::MAP_PAGE_TEMPLATE)->render($customVariables + array('googleMapsAPIKey' => $this->config->getGoogleMapsAPIKey(), 'pageTitle' => implode(' - ', $pageTitle)));
 }