The example CA now has more realistic 2 levels with a root CA and a sub CA.
Setup script and ca.cnf has been changed to create a root CA and a sub CA
that is signed by the root CA. The sub CA is used for signing the end entity
certificates. Example CA directory has been changed to example_ca for better
readability.
This commit adds a simple go backend calling openssl ca to sign CRS
coming from the client. The JavaScript code in src/index.html has been
extended to send requests to the sign endpoint and display the resulting
certificate in a separate div element.
A script setup_example_ca.sh and an openssl configuration file ca.cnf
has been added to allow quick setup of a simple example CA.
