Documentation: Revert renaming installation guide. Use legacy name installation_guide.html to be semantically more explicit *and* avoid renaming x language variable which contain the filename

public/documentation/index.html

@@ -33,7 +33,7 @@
     <h1>Chamilo 2.x - Documentation</h1>
     <ul>
         <li>
-            <a href="install.html">Installation guide (EN)</a>
+            <a href="installation_guide.html">Installation guide (EN)</a>
         </li>
         <li>
             <a href="https://docs.chamilo.org/">Manuals for teachers, admins and developers (several languages available through menu)</a>

public/main/install/index.php

@@ -117,7 +117,7 @@ $institutionForm = 'My Organisation';
 $session_lifetime = 360000;
 //$installLanguage = isset($_SESSION['install_language']) ? $_SESSION['install_language'] : 'english';
 $installLanguage = '';
-$installationGuideLink = '../../documentation/install.html';
+$installationGuideLink = '../../documentation/installation_guide.html';
 
 // Setting the error reporting levels.
 error_reporting(E_ALL);

src/CoreBundle/Controller/Admin/IndexBlocksController.php

@@ -675,7 +675,7 @@ class IndexBlocksController extends BaseController
         ];
         $items[] = [
             'class' => 'item-installation-guide',
-            'url' => $this->generateUrl('legacy_main', ['name' => '../documentation/installation.html']),
+            'url' => $this->generateUrl('legacy_main', ['name' => '../documentation/installation_guide.html']),
             'label' => $this->translator->trans('Installation guide'),
         ];
         $items[] = [