7.0 export partner and address

Completion of the magentoerpconnect_export_partner module to fix the export of partners and add the export of addresses.

This PR depend of this one and need to be merged after : 

* [ ] https://github.com/OCA/connector-magento/pull/33

Initial proposal on lauchpad : 
https://code.launchpad.net/~akretion-team/openerp-connector-magento/7.0-export-partner-and-address/+merge/224180
Well, here, ``` if not rel_binder.to_backend(binding_id):```
We do not pass the wrap argument because we pass the binding id, so it won't return None. Even if we passed it, it wouldn't because
We just create the binding in the export_dependency method so it exists.

The to_backend method return  ```magento_record['magento_id']``` which is False because the address is not yet created in magento.

I am not sure to understand exactly the objective of the condition, but I guess the goal is to export only if the record is not on magento yet. In this case, we expect the  ```rel_binder.to_backend(binding_id)``` to return False.