yahns 1.12.1 - more TLS fixes

Most notably release fixes TLS output buffering for large
responses to slow clients.  For Rack HTTPS users,
env['SERVER_PORT'] also defaults to 443 properly unless the
Host: request header specifies differently.

Also, the extras/autoindex change is to make our own directory
listing look nicer as we use Let's Encrypt and don't want to
waste space listing ".well-known/" directory contents on:

    https://yahns.yhbt.net/

Yes, we really do care how our homepage looks!

6 changes since v1.12.1:
      extras/autoindex: support hiding dotfiles
      fix output buffering with SSL_write
      https: ensure SERVER_PORT defaults to 443
      test_ssl: check SERVER_PORT when parsed from Host: header
      doc: mention kqueue/kevent alongside epoll
      doc: more minor updates