(functionality now provided by dns_blacklists.cfg)

The hardcoded RBL functionality has been replaced with dns_blacklist.cfg.
Created option bits: MAIL_OPT_DNSBL_IGNORE and REFUSE.
If neither is set, mail is marked with optional subject flag and X-RBL header.

Fixed subject, to, and from CRCs in message base index (lowercase conversion).
Fixed memory leak if message base constructor failed.
Added support for USENET Path and Newsgroups header fields.
Added optional parameter to get_msg_header to force regeneration of msg-ID.
 - this solves the dupe-loop problem in newslink.js with messages imported with
 - QWKnet MSGIDs.

Added support for USENET path and newsgroups header fields.

"path" and "newsgroups" header fields.

upper/lower case strings in new user-supplied strings.
Removed unused toggle options: UQ_COMP (computer type) and UQ_MC_COMP
(multiple choice computer questions).
Added advanced options: user database backups and mail database backups.

upper/lower case strings in new user-supplied strings.

is not properly formatted ("name" <addr> for example).

Backup files are named filename.ext.# instead of filename.ex#.

(to maintain threading across networks).

reply_id property is not created if it doesn't exist in the msg header.
msg.id is based on the time the message was imported rather than written.