Checkmk Werk 15655: host: addition of show single host endpoint

ID: 15655 Title: host: addition of show single host endpoint Component: REST API Level: 1 Class: New feature Version: 2.3.0b1 Prior to this werk, the list hosts collection endpoint returned hosts which also included a link to the respective host. Following those links returned an error as the endpoint did not exist. This is now added with this werk.