Moving the storage of referrer information to main authorization check instead of doing it in the authentication source

Signed-off-by: Ralph Krimmel <rkrimme1@gwdg.de>

lib/errors.js

@@ -6,6 +6,8 @@ module.exports = {
     if (req.user) {
       responseError(res, '403', 'Forbidden', 'oh no.')
     } else {
+      if (!req.session) req.session = {}
+      req.session.returnTo = req.originalUrl || config.serverUrl + '/';
       req.flash('error', 'You are not allowed to access this page. Maybe try logging in?')
       res.redirect(config.serverURL + '/')
     }