Call the certificates .pem and the keys .key; use contrib/gencert to generate the certificates and provide a GENCERT_FLAGS knob so that regress can be run with EC keys (GENCERT_FLAGS=-e). Still no automatic way of testing with both RSA and EC keys.

some CI envs don't like `listen on localhost' but tolerate INADDR_ANY or IN6ADDR_ANY_INIT.

Listening by default on all the addresses is so bad I don't know why I haven't changed this before. Anyway. Add a `listen on $hostname port $port' syntax to the config file and deprecate the old "port" and "ipv6" global setting. Still try to honour them when no "listen on" directive is used for backward compatibily, but this will go away in the next next version hopefully. At the moment the `listen on' in server context don't filter the host, i.e. one can still reach a host from a address not specified in the corresponding `liste on', this will be added later.

it's just not worth it to inflict this breaking change to the users.

will help in future restructuring to have fixed-size objects.

-d is `debug' (run in the foreground) -f to load the configuration file adjust regress and contrib accordingly