title: Migration tool for appsettings.json config
body: <p>I have a hosted asp.net core project. And every time a new version has to be deployed and its <strong>appsettings</strong> config has some structural changes (added new keys or renamed some old config keys for example) - I need to manually add/rename these new keys in the existing production configuration. Is there any tool that allows creating config migrations and then running them to update existing config files (something like entity framework migration system for DB structure changes but for appsettings.json config)?</p>