Set expiry for translation tab cookie

Issue #1059
Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/static/loader-bootstrap.js

@@ -540,7 +540,7 @@ $(function () {
     /* Store active translation tab in cookie */
     $('.translation-tabs a[data-toggle="tab"]').on('shown.bs.tab', function(e) {
         Cookies.remove('translate-tab', { path: '' });
-        Cookies.set('translate-tab', $(this).attr('href'), { path: '/'});
+        Cookies.set('translate-tab', $(this).attr('href'), { path: '/', expires: 365 });
     });
 
     /* Navigate to a tab when the history changes */