rest: Pass the project name to middleware config
rest: Pass the project name to middleware config

Now oslo.middleware middlewares can read options from the application
configuration file if we pass the project name in the 'oslo_config_project'
option.

This change adds that. Now all oslo.middleware middlewares are usable
with gnocchi.

Change-Id: Id9625622be2727bf07c40d5b70c72282a1f6c7b8

sileht/gnocchi,sileht/gnocchi,gnocchixyz/gnocchi,leandroreox/gnocchi,leandroreox/gnocchi,gnocchixyz/gnocchi