IMAP operation progress information.
The class supplies both the two IMAP progress types, generic and synchronisation.
The IMAP4 server MTM owns two IMAP4 sessions that are used independently of each other to perform 'background' and 'foreground' operations. In a typical situation, the user may be downloading the body parts of a message (populating) in the foreground whilst in the background a full synchronisation may be underway. In this scenario, the generic progress will give an indication of the 'foreground' activity and the synchronisation progress will give an indication of the 'background' progress. The synchronisation progress component of the compound progress will always show the synchronisation progress irrespective of whether the synchronisation is running in the foreground or the background.