I think that installing a non-certified module to do this is overkill considering it is possible just with configuration. See http://help.openerp.com/question/2676/company-under-company/

Well basically your are doing the same, in a module perhaps its overkill but it is reusable. In my module I also separated affiliates under an other tab than contacts.

Yannick, yes if it's the only thing you have in that module, it's the same indeed.

@Fabrice: I do not call changing the views from the view editor 'configuration'. What about the migrations? If you modify all your views from the client, are you sure they will be kept? That's always better to do that in addons, even if this 1 change in 1 view. I think that will never be overkill.

@Guewen: I agree that it is a better practice to make the change in a separate module. But it is only possible for developers. This is why I said it is overkill: it is overkill to have to call a developer to make a field visible. And it is also completely possible to make this change from the view editor AND make sure that it will go through updates and migrations if you do it correctly (inherit and add fields "inside"). This way, you are sure they will be kept because an update will reset the original views, not the ones you have created.

An installation description would be nice

@wjn please refers to this question How to install openerp app from launchpad

Thank you, that's a more extended and better approach then I did (I copied it directly to the addons path, on a test server of course).