7.0 change public holiday

Add country and states
Resubmit of https://code.launchpad.net/~initos.com/openerp-hr/7.0-change-public-holiday/+merge/224610
You can rework this in this way:

```
states_filter = [('holidays_id', 'in', ph_ids)]
if not employee or not employee.address_id.state_id:
    states_filter.append(('state_ids', '=', False))
else:
    states_filter += ['|', ('state_ids', '=', False), ('state_ids.id', '=', employee.address_id.state_id.id))
```