Added an optional command-line switch called swaggerUiPath....

...,  If non-blank it specifies a base path in which the output should be saved -- as individual JSON files, rather than as a hashmap in a single docs.go file. First the overall API info is saved as index.json in the root of the base path. Then, the API specification for each sub-api is saved as index.json in a sub-folder that matches the sub-api (resource) name. This is all consistent with using a "data" folder with SwaggerUI "out of the box". (No issue number.)