Bugfix: there's a couple of places in SimpleSAML\Utils\HTTP where we should...

Bugfix: there's a couple of places in SimpleSAML\Utils\HTTP where we should use the host AND port if the latter is not the default one, but we are only using the host. These are the case for evaluating the 'trusted.url.domains' configuration options (we should allow the host and port we are reachable in, but not other ports in the same host) and the method that returns the host with path, which should include the port if that's not standard (the documentation of the method already says so).