Prevent logout issue after page was cached (prasathmani#1004)

Logout may not work otherwise, browser reloads cached page from disk instead of sending GET request ?logout=1 to server.

tinyfilemanager.php

@@ -262,7 +262,7 @@
         mb_regex_encoding('UTF-8');
     }
 
-    session_cache_limiter('');
+    session_cache_limiter('nocache'); // Prevent logout issue after page was cached
     session_name(FM_SESSION_ID );
     function session_error_handling_function($code, $msg, $file, $line) {
         // Permission denied for default session, try to create a new one