maillist_fetch_IMAP should be disabled by default, also used functions in enable/disable some other core feature scheduled tasks

Signed-off-by: emanuele <emanuele45@gmail.com>
cant => can't or cannot :P

Signed-off-by: emanuele <emanuele45@gmail.com>
Moar checks for imap

Signed-off-by: emanuele <emanuele45@gmail.com>