Remove Mistral references

Remove all Mistral references that was left behind
when the project was created.

Change-Id: I6860e4a7f47600651456b66c4fbe301feef04676

qinling/api/access_control.py

@@ -44,14 +44,14 @@ def enforce(action, context, target=None, do_raise=True,
     :param action: String, representing the action to be checked.
                    This should be colon separated for clarity.
                    i.e. ``workflows:create``
-    :param context: Mistral context.
+    :param context: Qinling context.
     :param target: Dictionary, representing the object of the action.
                    For object creation, this should be a dictionary
                    representing the location of the object.
                    e.g. ``{'project_id': context.project_id}``
     :param do_raise: if True (the default), raises specified exception.
     :param exc: Exception to be raised if not authorized. Default is
-                mistral.exceptions.NotAllowedException.
+                qinling.exceptions.NotAllowedException.
 
     :return: returns True if authorized and False if not authorized and
              do_raise is False.

qinling/api/service.py

@@ -25,7 +25,7 @@ LOG = logging.getLogger(__name__)
 
 
 class WSGIService(service.ServiceBase):
-    """Provides ability to launch Mistral API from wsgi app."""
+    """Provides ability to launch Qinling API from wsgi app."""
 
     def __init__(self):
         self.app = app.setup_app()

qinling/db/sqlalchemy/migration/cli.py

@@ -23,7 +23,7 @@ from oslo_config import cfg
 from oslo_utils import importutils
 import six
 
-# We need to import mistral.api.app to
+# We need to import qinling.api.app to
 # make sure we register all needed options.
 importutils.try_import('qinling.api.app')