[FIX] base_external_referentials strip commas when evaluating a str/unicode list
[FIX] base_external_referentials strip commas when evaluating a str/unicode list

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