#### GssapiNameAttributes

Enables the module to source Name Attributes from the client name
(authorization data associated with the established context) and exposes them
as environment variables.

Value format: ENV_VAR_NAME ATTRIBUTE_NAME

This option can be specified multiple times, once for each attribute to expose.
The Special value "json" is used to expose all attributes in a json formatted
string via the special environment variable GSS_NAME_ATTRS_JSON
The environment variable GSS_NAME_ATTR_ERROR is set with the Gssapi returned
error string in case the inquire name function fails to retrieve attributes,
and with the string "0 attributes found", if no attributes are set.

#### Example
    GssapiNameAttributes json
    GssapiNameAttributes RADIUS_USER_NAME urn:ietf:params:gss:radius-attribute 1
    GssapiNameAttributes EPPN urn:ietf:params:gss:federated-saml-attribute urn:oasis:names:tc:SAML:2.0:attrname-format:uri urn:oid:1.3.6.1.4.1.5923.1.1.1.6