Comment 9 for bug 1151947

After extra internal discussion, it seems it would definitely be better to keep the `ìs_company` flag as meaning exactly what its name implies, so that it can be used for legal reasons etc. Please disregard my previous comment (I've hidden it for clarity).

So what should be changed in 7.0: we should make sure nothing prevents having addresses or contacts for a regular partner as well, i.e:
- change the fact that currently if the `is_company` flag is unchecked, all addresses/contacts are discarded after each modification
- review all places where the "is_company" flag is used to make sure it is not exclusive with the presence of children
- review the places where the `parent_id` field is used to make sure it does not preclude having a parent that does not have a `is_company` checked.
- change the mini-form view that is displayed by default for the contacts, e.g. by adding the `use_parent_address` field and make it toggle the extra address fields

Then we should ideally add an extra config option in the settings such as "Allow regular users to have multiple contacts or addresses", associated with a group that makes the contacts visible all the time. This is unfortunately a change in the data model (for the extra setting) and cannot be done in 7.0 without adding an extra module.

For trunk we'll do that in `base` directly, and for 7.0 an extra module should be written to accomplish the same thing.