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
But I think you could pop the 'partner_id' from the data right in exporter._create() instead of in the adapter so the public interface of the adapter is explicit. Only an idea... maybe not the best one. It seems to me that the sooner we can extract the partner id the better it would be because it means less steps to remember the "where does comes this partner_id and why is it in the data".