add infra-structure for automatic schema migrations
auto-migration for database schema
IMAP: finish up LOGINDISABLED
IMAP: fix buffer size in search-date
IMAP: fix base-subject scanner
IMAP: subject search use base-subject
IMAP: add functional test for searching header
IMAP: lower-case base-subject for case-insensitive search and sort
IMAP: small bugfix in sequence-set scanner
re-open log-files using SIGHUP