New Features:
- Multiple bindings for each service
  Use comma-separated interfaces on Interface= lines in the ini file.
  Default is now "0.0.0.0,::"
- IPv6 support
- TLS support for the webserver and (non-static) services
  New TLS option in services.ini (ie: Options=TLS)
- Decrease LEN_SCAN_CMD to 35 chars, increase the CID field to 45 chars,
  and rename the MAIL_CMD string to IPADDR.  I think this frees up the
  note field for SysOp use.

by properly const-ifying the appropriate functions and variables.

Not yet tested on Win32

Changes order of members in sbbs_t... all libs need rebuilding.

example, [telnet|rlogin] would set the socket options for either telnet or
rlogin servers, while [telnet] would set the socket options only for the telnet
server.

(replacing sockopts.cfg).

ftp_put() now immediately fails if the file doesn't exist.
ftp_put() now uses a case-insensitive file existence check/case fix.

unused (passing NULL).

Makes the poll/yield loops unnecessary.

- fixes problem with detecting bad/blank DNS server IP address.

server before sending STOR command.

server before sending LIST/RETR command.

struct before calling bind() which caused intermittent failures on FreeBSD.

that keeps proper track of the number of open socket descriptors.

connection BEFORE the LIST/RETR/STOR command is sent.

when telnet server network interface is set to 0 (<any>).

This should fix the problem in the QNET-FTP module timing-out waiting for the BBS to create the QWK packet.