imapserver.py: Make severity var available where it is needed
imapserver.py: Make severity var available where it is needed

We we using the variable 'severity' in a few places to throw
OfflineImapErrorrs of severity REPO. Somehow, that variable is now not
accessible in all places that refer to it, so we move where it is
defined to before all the 'if' checks which might make use of it.

Signed-off-by: Sebastian Spaeth <98dcb2717ddae152d5b359c6ea97e4fe34a29d4c@SSpaeth.de>
Signed-off-by: Nicolas Sebrecht <347709267ddd1958560c4c317ea3fd613f10a719@laposte.net>

frioux/offlineimap,frioux/offlineimap