[REF] connector/unit/binder.py: avoid confusion by renaming backend_id to external_id
[REF] connector/unit/binder.py: avoid confusion by renaming backend_id to external_id

sylvain-garancher/connector,mohamedhagag/connector,BT-ojossen/connector,Antiun/connector,anybox/connector,brain-tec/connector,fevxie/connector,fevxie/connector,gurneyalex/connector,dvitme/connector,anybox/connector,acsone/connector,zhaohuaw/connector,BT-ojossen/connector,zhaohuaw/connector,MindAndGo/connector,js-landoo/connector,dvitme/connector,sylvain-garancher/connector,Antiun/connector,BT-fgarbely/connector,mohamedhagag/connector,js-landoo/connector,acsone/connector,guewen/connector,MindAndGo/connector,esousy/connector,maljac/connector,open-synergy/connector,Endika/connector,maljac/connector,hugosantosred/connector,BT-jmichaud/connector,guewen/connector,BT-jmichaud/connector,open-synergy/connector,acsone/connector,esousy/connector,gurneyalex/connector,brain-tec/connector,brain-tec/connector,BT-fgarbely/connector,hugosantosred/connector,Endika/connector