SAML2-SP: Add authentication processing filter support.
SAML2-SP: Add authentication processing filter support.

vivekrajenderan/simplesamlphp,tectronics/simplesamlphp,tectronics/simplesamlphp,tectronics/simplesamlphp,vivekrajenderan/simplesamlphp,tectronics/simplesamlphp,vivekrajenderan/simplesamlphp,vivekrajenderan/simplesamlphp,vivekrajenderan/simplesamlphp,tectronics/simplesamlphp