fixes #3674 - revert system -> host for URI.parse
fixes #3674 - copy existing routes to legacy routes
fixes #3674 - modify legacy routes :path => :hosts and :as => :old_hosts
fixes #3674 - modify api v1 views to include hostgroup_id for api/hosts/:id
fixes #3674 - changed ERF51-2640: to ERF51-7324: for passing test ???