Merge pull request #17 from guewen/7.0-add-boundary-to-batch-jobs

Add a 'to date' boundary to batch jobs
Prevent to create duplicate bindings on invoices

The correction made at becc1bf2 was not working because it was
doing a 'continue' on the inner loop but not on the outer loop.
Merge remote-tracking branch 'guewen/invoice-binding-unique' from
https://github.com/OCA/connector-magento/pull/39

Conflicts:
	magentoerpconnect/i18n/fr.po
	magentoerpconnect/i18n/magentoerpconnect.pot