* To describe working configurations of openstack (which code branches work together? what do config files look like for those branches?)
* To make it easier for developers to dive into openstack so that they can productively contribute without having to understand every part of the system at once
* To make it easy to prototype cross-project features
You can tweak environment variables by creating file name 'localrc' should you need to override defaults. It is likely that you will need to do this to tweak your networking configuration should you need to access your cloud from a different host.