Update travis configuration
Update travis configuration

use sudo: false to enable container build
use cache: pip to cache pip packages

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