Move i18n module to a private name

The i18n module for this library is private to the library and should
never be used by outside code. Rename the module to reflect this.

Change-Id: I39149056daeeb27428b938fb9cd7278cd42f2444

oslo_middleware/catch_errors.py

@@ -18,8 +18,8 @@ import logging
 import webob.dec
 import webob.exc
 
+from oslo_middleware._i18n import _LE
 from oslo_middleware import base
-from oslo_middleware.i18n import _LE
 
 
 LOG = logging.getLogger(__name__)

oslo_middleware/healthcheck/disable_by_file.py

@@ -16,8 +16,8 @@
 import logging
 import os
 
+from oslo_middleware._i18n import _LW
 from oslo_middleware.healthcheck import pluginbase
-from oslo_middleware.i18n import _LW
 
 LOG = logging.getLogger(__name__)
 

oslo_middleware/sizelimit.py

@@ -22,8 +22,8 @@ from oslo_config import cfgfilter
 import webob.dec
 import webob.exc
 
+from oslo_middleware._i18n import _
 from oslo_middleware import base
-from oslo_middleware.i18n import _
 
 
 _oldopts = [cfg.DeprecatedOpt('osapi_max_request_body_size',

tox.ini

@@ -37,4 +37,4 @@ ignore = E123,E125,H305,H803,H904
 exclude=.venv,.git,.tox,dist,doc,*lib/python*,*egg,build,__init__.py
 
 [hacking]
-import_exceptions = oslo_middleware.i18n
+import_exceptions = oslo_middleware._i18n