7.0 Add account companyweb

Add Account_companyweb addons
You can get the company_id for the user by calling:
``` python
company_id  = self.pool['res.company']._company_default_get(cr, uid, context=context)
```
Since we need to get the company_id for a specific model,  I wonder if it would be safer to call this method passing in the model.
```python
company_id  = self.pool['res.company']._company_default_get(
    cr, uid, object='account.account', field='company_id' context=context)
```