title: Combine multiple swagger files
body: <p>I was provided Swagger 2.0 json files for a RESTful API my project is using. The provider does not have SDK, so I'm using the Swagger files to generate a starting point to use for integrating with the service. It's split into 50+ files, grouped by collections of endpoints. How would I combine these into a single JSON or YAML file that conforms to the spec so I can generate SDK for all endpoints at once?</p>