configure openssl to accept proxy certs

docker/assets/nginx.conf

src/ngx_http_voms_module.cpp

t/eec_cert.t

t/eec_subject.t

t/encoding.t

t/expired.t

t/expired_ac.t

t/no_ac.t

t/no_ssl.t

t/no_ta.t

t/ssl_no_client_authn.t

t/untrusted_ac.t

t/valid_ac.t