Some bsddb changes

* allow to use bsddb3 as database via a config setting
  * set async write to disk to improve speed, eg import * 40


svn: r16446

src/plugins/lib/libgrdb.py

@@ -36,7 +36,11 @@ import random
 import locale
 import os
 from sys import maxint
-from bsddb import db
+import config
+if config.get('preferences.use-bsddb3'):
+    from bsddb3 import db
+else:
+    from bsddb import db
 from gen.ggettext import gettext as _
 
 import logging