* Remove @EnableDiscoveryClient and @EnableEurekaClient as there are now optional.  Fixes #2241.

In addition to `eureka.instance.hostname` property you can now defined `sidecar.hostname` in order to set different hostname from application and its sidecar.
However if `eureka.instance.hostname` is present it will override `sidecar.hostname`.

Fixes #981

Fixes gh-1205

fixes gh-847

Implements forwarding of eureka CacheRefreshedEvent as HeartbeatEvent,
rather thank serialization hack.  Uses new Eureka DI functionality
(mostly there, some issues). Updates EurekaJacksonCodec to be
"DataCenterAware". Reference EurekaClient interface rather than
DiscoveryClient class.

fixes gh-349

Added a LocalApplicationHealthCheckHandler that checks the local app and sends the appropriate status to eureka.

fixes gh-251

fixes gh-225

fixes gh-98

Handle InstanceRegisteredEvent and RefreshScopeRefreshedEvent in ZuulHandlerMapping rather than ProxyRouteLocator.
Move /routes endpoint out of ZuulHandlerMapping into RoutesEndpoint (because of a problem when I added @RefreshScope to ZuulHandlerMapping)

Fire InstanceRegisterEvent after eureka registration, then components can listen for that event and safely access DiscoveryClient.

updated sidecar so the health and info urls go to sidecar, but homepage and non-secure-port go to local app