As Denver officials continue narrowing down the list of public and private properties that could host the so-called micro-communities that would house people living homeless on the city’s streets, Mayor Mike Johnston on Wednesday provided the most detailed picture yet of how those communities could be organized. Holding his fourth news conference since declaring a state of emergency around homelessness in Denver less than a month ago, Johnston said the city is seeking bids from nonprofit organizations that would be willing to operate and provide support services to micro-communities.