IMAP class: don't suggest multithreading in single-threaded mode

Signed-off-by: Eygene Ryabinkin <rea@codelabs.ru>

offlineimap/folder/IMAP.py

@@ -23,6 +23,7 @@ import time
 from sys import exc_info
 from .Base import BaseFolder
 from offlineimap import imaputil, imaplibutil, OfflineImapError
+from offlineimap import globals
 from offlineimap.imaplib2 import MonthNames
 
 
@@ -53,7 +54,7 @@ class IMAPFolder(BaseFolder):
             imapobj.select(self.getfullname(), readonly = True, force = force)
 
     def suggeststhreads(self):
-        return 1
+        return not globals.options.singlethreading
 
     def waitforthread(self):
         self.imapserver.connectionwait()