Robustness: safer RainTPL directory handling

Relates to https://github.com/shaarli/Shaarli/issues/845
Relates to https://github.com/shaarli/Shaarli/issues/846
Relates to https://github.com/shaarli/Shaarli/pull/909

Signed-off-by: VirtualTam <virtualtam@flibidi.net>

application/ApplicationUtils.php

@@ -168,14 +168,15 @@ class ApplicationUtils
     public static function checkResourcePermissions($conf)
     {
         $errors = array();
+        $rainTplDir = rtrim($conf->get('resource.raintpl_tpl'), '/');
 
         // Check script and template directories are readable
         foreach (array(
             'application',
             'inc',
             'plugins',
-            $conf->get('resource.raintpl_tpl'),
-            $conf->get('resource.raintpl_tpl').'/'.$conf->get('resource.theme'),
+            $rainTplDir,
+            $rainTplDir.'/'.$conf->get('resource.theme'),
         ) as $path) {
             if (! is_readable(realpath($path))) {
                 $errors[] = '"'.$path.'" directory is not readable';

application/ThemeUtils.php

@@ -22,6 +22,7 @@ class ThemeUtils
      */
     public static function getThemes($tplDir)
     {
+        $tplDir = rtrim($tplDir, '/');
         $allTheme = glob($tplDir.'/*', GLOB_ONLYDIR);
         $themes = [];
         foreach ($allTheme as $value) {