Helper class to detect the deployment color and if current instance is active or not. The logic to detect if instance is active or
inactive is based on the configuration in etcd under key
/vhosts/local-svc.leanix.net/deploy_current or
/vhosts/local-eam.leanix.net/deploy_current. In oder to use this class you have to specify:
* ETCD_SERVER : the etcd server, e.g. '192.168.59.103:4001'
* CONTAINER_COLOR: 'green', 'blue' or 'white'
* VIRTUAL_HOST : the virtual host name e.g. 'local-eam.leanix.net' (default: local-svc.leanix.net)