Update documentation of CLI tool

README.md

@@ -213,4 +213,7 @@ Common usage:
 - Specify a swagger definition file: `./bin/swagger-jsdoc -d example/swaggerDef.js` - could be any .js or .json file which will be `require()`-ed and parsed/validated as JSON.
 - Specify files with documentation: `./bin/swagger-jsdoc example/routes.js example/routes2.js` - free form input, can be before or after definition
 - Specify output file (optional): `./bin/swagger-jsdoc -o output.json` - swaggerSpec.json will be created if this is not set.
-- Watch for changes: `./bin/swagger-jsdoc -d example/swaggerDef.js example/routes.js example/routes2.js -w` - this will add the definition file swaggerDef.js and its arguments routes.js and routes2.js in a watch process, re-generating swagger spec on changes.
+- Watch for changes: `./bin/swagger-jsdoc -d example/swaggerDef.js example/routes.js example/routes2.js -w` - start a watch task for input files with API documentation.
+This may be particularly useful when the output specification file is integrated with [Browsersync](https://browsersync.io/)
+and [Swagger UI](http://swagger.io/swagger-ui/). Thus, the developer updates documentation in code with fast feedback in an
+interface showing an example of live documentation based on the swagger specification.