Change validators to use the validator_context

Change InstanceKeys to take a namedtuple for context

util/config/validators/validate_torrent.py

@@ -11,15 +11,16 @@ class BittorrentValidator(BaseValidator):
   name = "bittorrent"
 
   @classmethod
-  def validate(cls, config, user, user_password, app):
+  def validate(cls, validator_context):
     """ Validates the configuration for using BitTorrent for downloads. """
+    config = validator_context.config
+    client = validator_context.http_client
+
     announce_url = config.get('BITTORRENT_ANNOUNCE_URL')
     if not announce_url:
       raise ConfigValidationException('Missing announce URL')
 
     # Ensure that the tracker is reachable and accepts requests signed with a registry key.
-    client = app.config['HTTPCLIENT']
-
     params = {
       'info_hash': sha1('test').digest(),
       'peer_id': '-QUAY00-6wfG2wk6wWLc',