Moved custom ToSql trait including Send + Sync from lib.rs to sql.rs.
Replaced most params! and paramsv! macro usage with tuples.
Replaced paramsv! and params_iterv! with params_slice!,
because there is no need to construct a vector.
This makes the contact ID its own newtype instead of being a plain
u32. The change purposefully does not yet try and reap any benefits
from this yet, instead aiming for a boring change that's easy to
review. Only exception is the ToSql/FromSql as not doing that yet
would also have created churn in the database code and it is easier to
go straight for the right solution here.
`imap` table maps Message-IDs to UIDs on the server. `dc_receive_imf`
no longer gets the UID of the message as an argument and does not
insert the folder and UID of the message into the `msgs`
table. `server_folder` and `server_uid` columns in `msgs` table are
deprecated.
MoveMsg and DeleteMsgOnImap jobs are removed. Now messages are moved
and deleted only in the `fetch_move_delete` procedure that consults
the `target` column of the `imap` table to determine where the message
should go.
Where the message should go is determined after prefetching by the
`imap::target_folder()` procedure. Messages are only downloaded once
they reach their target folder to avoid race conditions in multidevice
setting, such as:
1. One device trying to FETCH the message while the other tries to
MOVE it.
2. One device marking the message as \Seen in the Inbox while the
other has already copied unseen message to the Movebox and is going to
delete the \Seen message in the Inbox.
3. Device downloads the message from the Inbox while there are newer
messages in the Movebox placed there by the other device, thus
processing the messages out of order.
* check update timestamps for signatures, user-avatars, ephemeral-settings, last-subject
* check update timestamp for group-avatars
* check update timestamp for group-names
* check update timestamp for memberlist
* check update timestamp for protection-settings
* add a more advanced test
* add another more advanced test
* set last-subject-timestamp more carefully
* bubble up errros from set_*timestamp() and check for from_id==0 before
* simplify Params::set_i64()
* remove comment that is more confusing than helpful
* use update_timestamp() wording consistently
