Added widget install documentation section.
Added widget install documentation section.

carlos-reynosa/magento-html5-webrtc-customer-service-module,carlos-reynosa/magento-html5-webrtc-customer-service-module,carlos-reynosa/magento-html5-webrtc-customer-service-module,carlos-reynosa/magento-html5-webrtc-customer-service-module,carlos-reynosa/magento-html5-webrtc-customer-service-module