text: Title: Ability to modify swagger strings
  Body: The built-in openapi support is great! Kudos to that. However, it would be nice if there were ways to modify more swagger strings such as page title, `default`, `description` etc. Not a very important feature but would be nice to have to make swagger docs more customizable. 
  
  I am thinking passing common variables within `responder.API` along with already existing "title" and "version"? 