Gromox 2.18

Fixes:

• exmdb: synthesized PR_RTF_COMPRESSED properties (in relation to the dbg_synthesize_content config directive) had an incomplete header
• oxcmail: repair inadvertent propid/proptag swap causing TNEF export to fail
• mbop/purge-softdelete: make pathspec SENT/2022 actually work
• imap: messages delete events from OL/g-web now make it to IMAP clients

Enhancements:

• midb: propagate folder change events; IMAP clients now recognize when a message was deleted in g-web/Outlook
• http: RFC 7617 support for the Basic authentication header line
• nsp: allow connections from Windows with UTF-8 locale
• midb: removal of seqid renumbering, which speeds up IMAP SELECT/LIST/FETCH commands.
• authmgr: PAM is now offered as an authentication backend