- Use an environment variable to point at the configuration file while
strating gpg-mailgate.py.
- Unify paths: store temporary config, logs and anything else under 'test'
directory.
- Configure more tests (RSA, Ed25519).
- Add test descriptions to be shown before they're started.
Provide a simple Python script that would linsten on a given port and print to
standard output any message received via SMTP on that port.
This script will then be used to automatically test gpg-mailgate with different
scenarios (unknown recipient key, RSA key, elliptic curve key).