HPCC-11764 Dafilesrv authentication and encryption on transport

Current dafilesrv uses unencrypted sockets which is not secure. This update
adds a new section to the environment.conf file to optionally specify that
dafilesrv and its clients should use SSL, and points to the cert file, key file
and provides an encrypted passphrase. If specified, dafilesrv and its clients
will enable secure sockets (openSSL) and communicate in a secure manner.

Signed-off-by: William Whitehead <william.whitehead@lexisnexis.com>
port is manipulate here (if 0) but listenep is not used.. having already been used in lines that proceed useSSL..
So this isn't going to have any effect.. unless listenep is already using the secure port..
.. which it happens to be, see next comment.