SAML2: Support configurable attribute encodings.
SAML2: Support configurable attribute encodings.

This option makes it possible to include raw XML in the attributes
sent to an SP. A new option is introduced: attributeencodings

Patch by Joakim Recht <jre@trifork.com>.

Rud5G/simplesamlphp,Rud5G/simplesamlphp,Rud5G/simplesamlphp,Rud5G/simplesamlphp