added and modified customization files to fix the shibboleth configuration

Dockerfile.dist

commul-customization/aai.js

commul-customization/aai_config.js

commul-customization/default-ssl

commul-customization/discojuiceDiscoveryResponse.html

commul-customization/fastcgi.conf

commul-customization/nginx.conf

commul-customization/shib_clear_headers

commul-customization/shibboleth2.xml

commul-customization/start_stack.sh

commul-customization/stop_stack.sh