wrap os.listdir() to decode utf-8 unicode into unicode objects

change all code locations using os.listdir() to use munkicommon.listdir()



git-svn-id: http://munki.googlecode.com/svn/trunk@941 a4e17f2e-e282-11dd-95e1-755cbddbdd66

code/client/makecatalogs

@@ -104,7 +104,7 @@ def makecatalogs(repopath):
     if not os.path.exists(catalogpath):
         os.mkdir(catalogpath)
     else:
-        for item in os.listdir(catalogpath):
+        for item in munkicommon.listdir(catalogpath):
             itempath = os.path.join(catalogpath, item)
             if os.path.isfile(itempath):
                 os.remove(itempath)