Fix Swagger version error in documentation
Fix Swagger version error in documentation

In `Customizing the swagger endpoints` section, second line in the first table has Swagger version `2.0`, but it should be `1.2`.
yelhouti/springfox,springfox/springfox,yelhouti/springfox,springfox/springfox,springfox/springfox,springfox/springfox,yelhouti/springfox