Deprecate web_framework option

We didn't quite get around to pulling out all of the old API
code before the end of the cycle so we should deprecate this
option to make sure people don't use it.

Change-Id: Idf9d497bbccdb89c6e5898611d1cad9a18b1bcbb
Implements: blueprint wsgi-pecan-switch

neutron/conf/common.py

@@ -118,6 +118,7 @@ core_opts = [
                 help=_('If True, then allow plugins that support it to '
                        'create VLAN transparent networks.')),
     cfg.StrOpt('web_framework', default='pecan',
+               deprecated_for_removal=True,
                choices=('legacy', 'pecan'),
                help=_("This will choose the web framework in which to run "
                       "the Neutron API server. 'pecan' is a new "

releasenotes/notes/web_framework_deprecation-f984b83a1366c5b1.yaml

@@ -0,0 +1,7 @@
+---
+deprecations:
+  - |
+    The web_framework option has been deprecated and will be removed during
+    Queens. This option was just added to make the transition to pecan easier
+    so there is no reason operators should be using the non-default option
+    anyway.