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`.
@@ -79,7 +79,7 @@ By default the swagger service descriptions are generated at the following urls
|=======================
|Swagger version | Documentation Url | Group
|1.2 | /api-docs | implicit *default* group
-|2.0 | /api-docs?group=external | *external* group via docket.groupName()
+|1.2 | /api-docs?group=external | *external* group via docket.groupName()
|2.0 | /v2/api-docs | implicit *default* group
|2.0 | /v2/api-docs?group=external | *external* group via docket.groupName()
|=======================
