Use the traditional "template" config key, update unit-tests

lib/Configuration.php

@@ -46,7 +46,7 @@ class Configuration
             'syntaxhighlightingtheme'  => '',
             'sizelimit'                => 10485760,
             'templateselection'        => false,
-            'templatedefault'          => '',
+            'template'                 => 'bootstrap',
             'info'                     => 'More information on the <a href=\'https://privatebin.info/\'>project page</a>.',
             'notice'                   => '',
             'languageselection'        => false,
@@ -79,13 +79,13 @@ class Configuration
             'markdown'           => 'Markdown',
         ),
         'available_templates' => array(
+            'bootstrap5',
             'bootstrap',
             'bootstrap-page',
             'bootstrap-dark',
             'bootstrap-dark-page',
             'bootstrap-compact',
             'bootstrap-compact-page',
-            'bootstrap5',
             'page',
         ),
         'traffic' => array(

lib/Controller.php

@@ -213,9 +213,10 @@ class Controller
         $this->_conf = new Configuration;
 
         $templates = $this->_conf->getSection('available_templates');
-        $template = $this->_conf->getKey('templatedefault');
+        $template = $this->_conf->getKey('template');
         TemplateSwitcher::setAvailableTemplates($templates);
         TemplateSwitcher::setTemplateFallback($template);
+
         // force default template, if template selection is disabled and a default is set
         if (!$this->_conf->getKey('templateselection') && !empty($template)) {
             $_COOKIE['template'] = $template;

lib/TemplateSwitcher.php

@@ -26,7 +26,7 @@ class TemplateSwitcher {
      * @static
      * @var    string
      */
-    protected static $_templateFallback = "bootstrap";
+    protected static $_templateFallback;
 
 
     /**