Previously, we were simply locking offlineimap whenever it was
running. Howver there is no reason why we shouldn't be able to invoke it
in parallel, e.g. to synchronize several accounts in one offlineimap
each.
This patch implements the locking per-account, so that it is possible to
sync different accounts at the same time. If in refresh mode, we will
attempt to loop three times before giving up.
This also fixes Debian bug #586655
Signed-off-by: Sebastian Spaeth <Sebastian@SSpaeth.de>
c7938dc081