This is more autoconf style

This way they don't show up in doveconf -n.

Finish the conversion to dict_init_auto() later.

The settings were already read at this point, so this didn't actually do
anything. Fixing the code to actually set it would break existing tests,
so just remove it.

If the mail store commit failed, the mail was not guaranteed to be saved.
We don't want to lose mails, even if e.g. a forward had just succeeded.

In that case, the header name and middle are empty, causing:

Panic: file edit-mail.c: line 820 (edit_mail_headers_parse): assertion failed: (body_offset > 0)

Fixed by skipping the bad header for parsing altogether.

This is needed when the mailbox is opened with EXAMINE and is a source
for the operation. imap_sieve_mailbox_run_copy_source() expects the
source mailbox's context to exist.

This avoids adding another Message-id if one is already present but
of bad quality.

Fixes compatibility with monolith.

.git can also be a file, pointing to an external location
for the actual git repository. This usually happens when
code is a subrepository.

It should be PACKAGE_NAME but that breaks too much now.