Task/saml2 conf for idp

[AlvaroVega]

Doc:
https://github.com/telefonicaid/fiware-keystone-spassword/blob/task/saml2_conf_for_idp/docs/iotp_saml_idp.md

New docker tag version: 1.12.0_saml2
https://hub.docker.com/layers/telefonicaiot/fiware-keystone-spassword/1.12.0_saml2/images/sha256-226d8c4349c62d14c2cf821a1a22f9a1b6b519f8e7a2be6d81f38fbbfa56a46b?context=repo

This is how use new env vars for docker-compose:

    - SAML_ENDPOINT=localhost:5001
    - SAML_CERTFILE=/etc/keystone/ssl/server.crt
    - SAML_KEYFILE=/etc/keystone/ssl/server.key
  volumes:
    - /home/iotp/server.crt:/etc/keystone/ssl/server.crt
    - /home/iotp/server.key:/etc/keystone/ssl/server.key

[AlvaroVega]

btw, this is how I create that certificate and key file for testing:

openssl genrsa -des3 -passout pass:xxxx -out server.pass.key 2048 
openssl rsa -passin pass:xxxx -in server.pass.key -out server.key
rm server.pass.key 
openssl req -new -key server.key -out server.csr \
    -subj "/C=ES/ST=DistritoT/L=Madrid/O=Telefonica/OU=Telefonica On premise platform/CN=telefonica.com"
openssl x509 -req -days 3000 -in server.csr -signkey server.key -out server.crt

[fgalan]

LGTM