[JAVA] [library: vertx] Fix improper initialization of main router in MainApiVerticle template

[ccozzolino]

Description

The current template for MainApiVerticle incorrectly instantiates the protected main Router and does not re-use that router member with the instantiated SwaggerRouter. I propose that we modify the template as follows:

Initiantiate the router as part of the init flow to ensure that the vertx instance is not null:

    Router router;

    @Override
    public void init(Vertx vertx, Context context) {
    	super.init(vertx, context);
    	router = Router.router(vertx);
    }

Also, pass the router member as the first parameter of the SwaggerRouter creation:

Router swaggerRouter = SwaggerRouter.swaggerRouter(router, swagger, vertx.eventBus(), new OperationIdServiceIdResolver());

Swagger-codegen version

2.2.3 and above

Swagger declaration file content or url

Command line used for generation

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