If this option is passed all requests that are not part of a replayed
conversation are killed. If the option is not passed, such requests are passed
through to the server as usual.
This means that certificates don't accumulate in the conf directory, users
don't have to clear certificates if the CA is regenerated, and the user can
specify a custom CA without invalid certificates being loaded inadvertently.
- Move option parsing utiliities to proxy.py
- Don't have a global config object. Pass it as an argument to ProxyServer.
- Simplify certificate generation logic.
- Use templates for config files. We can re-introduce customization of the
certificate attributes when we need them.
- Split CA and cert generation into separate functions.
- Generation methods provide an error return when generation fails.
- When the user explicitly specifies a certificate, we don't generate it, but
fail if it doesn't exist.
