Allow to pass port to `uri` value and replace Eureka port with this value

Allow to pass port as configuration parameter. For example uri would look like this:

	.route(p -> p
			.path("/sentence-service/**")
                        .filters( f-> f
				.rewritePath(
                        		"/sentence-service/(?<segment>.*)", "/$\\{segment}")
                                .retry( 3 )
						)
						.uri( "lb://SENTENCE:8081" )
				)
                .build();

In this case Gateway will fetch path info from Eureka, but will use port 8081

Extend ReactiveLoadBalancerClientFilter class. Check if port is passed. If so, replace port from Eureka with the one passed.

Start at ReactiveLoadBalancerClientFilter and trace how the route URI and Eureka instance data are combined. Done means a port supplied in the lb URI replaces Eureka's port while routing still uses Eureka path information; without a supplied port, existing behavior remains.