cleanup import statements and conform to PEP-8

Signed-off-by: Nicolas Sebrecht <nicolas.s-dev@laposte.net>

offlineimap/folder/Base.py

@@ -20,7 +20,6 @@ from offlineimap import threadutil
 from offlineimap.ui import getglobalui
 import os.path
 import re
-import sys
 import traceback
 
 class BaseFolder:

offlineimap/folder/LocalStatus.py

@@ -17,7 +17,8 @@
 #    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 
 from Base import BaseFolder
-import os, threading
+import os
+import threading
 
 magicline = "OFFLINEIMAP LocalStatus CACHE DATA - DO NOT MODIFY - FORMAT 1"
 

offlineimap/folder/Maildir.py

@@ -16,9 +16,11 @@
 #    along with this program; if not, write to the Free Software
 #    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 
-import os.path, os, re, time, socket
+import socket
+import time
+import re
+import os
 from Base import BaseFolder
-from offlineimap import imaputil
 from threading import Lock
 
 try:

offlineimap/folder/UIDMaps.py

@@ -17,10 +17,8 @@
 #    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 
 from threading import *
-from offlineimap import threadutil
-from offlineimap.threadutil import InstanceLimitedThread
 from IMAP import IMAPFolder
-import os.path, re
+import os.path
 
 class MappingFolderMixIn:
     def _initmapping(self):