Installation instructions do not work out of the box on Ubuntu 12.04

[timlinux]

Following your install instructions as they stand on the rtd site, I was not able to start the server getting this error:

Running service: 'http'
Error: Unknown command: 'run_gunicorn'

I resolved it by adding these lines to the top of my config file:

from sentry.conf.server import *
INSTALLED_APPS = INSTALLED_APPS + ( 
        'gunicorn',
        ) 

It would be great to update the docs to reflect this so that others in the same situation as myself dont need to struggle.