HTTP20Connection: Fix use of h2.settings

Fixes #372

Author: jayvdb

hyper/http20/connection.py

@@ -7,7 +7,7 @@
 """
 import h2.connection
 import h2.events
-import h2.settings
+from h2.settings import SettingCodes
 
 from ..compat import ssl
 from ..tls import wrap_socket, H2_NPN_PROTOCOLS, H2C_PROTOCOL
@@ -403,7 +403,7 @@ def _connect_upgrade(self, sock):
         with self._conn as conn:
             conn.initiate_upgrade_connection()
             conn.update_settings(
-                {h2.settings.ENABLE_PUSH: int(self._enable_push)}
+                {SettingCodes.ENABLE_PUSH: int(self._enable_push)}
             )
         self._send_outstanding_data()
 
@@ -424,7 +424,7 @@ def _send_preamble(self):
         with self._conn as conn:
             conn.initiate_connection()
             conn.update_settings(
-                {h2.settings.ENABLE_PUSH: int(self._enable_push)}
+                {SettingCodes.ENABLE_PUSH: int(self._enable_push)}
             )
         self._send_outstanding_data()