Implement EZP-21731: Some parts of eZ Publish use a loose test for checking for SSL

Instead of using a crafted test on port, use the more complete eZSys::isSSLNow() function, that also take into account configurations with an SSL reverse proxy.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Merge pull request #786 from guillaumelecerf/fix_ssl_test

Implement EZP-21731: Some parts of eZ Publish use a loose test for checking for SSL