fix api context load failure for cyborg-api runs by uwsgi

when deployable POST request[0] is made with admin user, it always returns
a 403 forbidden code. This patch fixes the bug.
The root cause is that "return app.app_factory(CONF)" in init_application()
will only load app:api_v1(see in [1]) and miss others filters:authtoken etc.

[0]: curl -g -i -X POST http://192.168.23.76/accelerator/v1/deployables
[1]: /etc/cyborg/api-paste.ini

Change-Id: I1498705271fe6de6fc42db9b73221d9794c36b2b

cyborg/api/wsgi_app.py

@@ -40,4 +40,4 @@ def init_application():
     LOG.debug("Configuration:")
     CONF.log_opt_values(LOG, log.DEBUG)
 
-    return app.app_factory(CONF)
+    return app.load_app()