[FIX] base_external_referential, fix the external_connection refactor, improve error mapping message, fix cast function for list
[FIX] base_external_referential, fix the external_connection refactor, improve error mapping message, fix cast function for list

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