Fix EZP-22446: redirect fails due to port eZSys::hostname()

JIRA: https://jira.ez.no/browse/EZP-22446

When using port in url, the host check by AllowedRedirectHosts will fail as the port is included in eZSys::hostname()

The fix makes it possible to return only the actual hostname in eZSys with a new optional parameter `$withPort`.
`eZModule::redirectTo()` uses this new parameter to make a strict host name comparison.