add persistent option for db

tiramisu/setting.py

@@ -34,7 +34,7 @@ ro_append = ('frozen', 'disabled', 'validator', 'everything_frozen',
 rw_remove = ('permissive', 'everything_frozen', 'mandatory')
 rw_append = ('frozen', 'disabled', 'validator', 'hidden')
 default_properties = ('expire', 'validator')
-default_storage = 'dictionary'
+storage_type = 'dictionary'
 
 
 class _const:
@@ -183,13 +183,13 @@ class Settings(object):
     "``Config()``'s configuration options"
     __slots__ = ('context', '_owner', '_p_')
 
-    def __init__(self, context, config_id, plugin_name):
+    def __init__(self, context, storage):
         # generic owner
         self._owner = owners.user
         self.context = context
-        import_lib = 'tiramisu.plugins.{0}.setting'.format(plugin_name)
+        import_lib = 'tiramisu.storage.{0}.setting'.format(storage_type)
         self._p_ = __import__(import_lib, globals(), locals(), ['Settings'],
-                              -1).Settings(config_id)
+                              -1).Settings(storage)
 
     def _getkey(self, opt):
         if self._p_.key_is_path: