Make remote client IP available on the RouteRequest

This allows for differentiated behaviour based on client remote ip.

Example:

    [self.httpServer handleMethod:@"GET" withPath:@"/" block:^(RouteRequest *request, RouteResponse *response) {
        RoutingConnection *connection = request.connection;
        NSString *connectedHost = [connection connectedHost];

        [response setStatusCode:200];
        [response setHeader:@"Content-Type" value:@"text/html"];
        [response respondWithString:[NSString stringWithFormat:@"Hello World [%@]", connectedHost];
    }];