A new property `spring.boot.admin.discovery.services` is added. It can
be used to restrict the services registered via discovery to a
whitelist (supporting simple patterns). Until now only blacklistin was
supported. The default whitelist permits all services.

https://github.com/spring-cloud/spring-cloud-netflix/pull/1372 has been
merged. So it is save to remove the local workaround.

Adds an new Notifier implementation for Let's Chat.

Since the Notifiers shouldn't throw exceptions, we let all extend the
AbstractEventNotifier which gets us a enabled property and catching
exceptions which may occur when notifiying.

My PR spring-cloud/spring-cloud-netflix#1448 has been merged into
Dalston, therefore we can remove our implementation and need to fix some
comile issues.

fixes #382

With this commit you can use simple patterns to match services to
ignore.
A pattern can look like this "foo*", "*foo", "foo*bar".

closes #377

The info is now fetched by the server on status change. This way the
info can be used in the notifications and also improves performance when
listing a huge amount of applications in the ui.

closes #349

With this change it is possible to include credentials in the instance
metadata which will then be used to access the client endpoints using
HTTP Basic authorization.

closes #359

With this commit you can now associate your applications with custom
metadata using `spring.boot.admin.client.metadata.*` sensitive values
are recognized by key and are masked in the http interface.

This can be useful in the future if there are instance specific settings
which should be used by the admin server, e.g. custom notification
recipients.

For now there is no extra imetadata view in the ui. The values are shown
in the environment view.

From this commit on the source from wich the application was registered
is remembered. We use this information for two things:
 * For applications which wasn't registered via the http-api the remove
   button is hidden.
 * The `ApplicationDiscoveryListener` only removes stale applications
   (those which are not anymore found via discovery) if the were registered
   via the `ApplicationDiscoeryListener`.

closes #328

The StatusInfo has a new details field. The StatusUpdater puts either the
reponse from the health endpoint or the exception message in the details.
This allows us to see the details over time (via the journal) and also to
use `em in a bit more mail notifications.

closes #329

With this commits the server no longer depends on the client. The
classes for the clients are moved to de.codecentric.boot.admin.client
package.
Since the perspective on applications is totally different from client
and server the model has been split apart.

What means this for users:
1) The client is no longer a transitive dependency for your admin server
you may need to add it explicitly to your dependencies, respectively
jolokia-core in case you're using discovery and want to use the jmx-bean
interface

2)In case you have cutomised parts of the client you need to reflect the
package change.

fixes #332

This CompositeRouteLocator allows extensions to add custom RouteLocators

 * Since the hystrix.stream incorrectly handles HEAD requests we had to change
   the detection for the hystrix-endpoint to a GET request.
   Issue https://github.com/Netflix/Hystrix/issues/1369

 * We need to improve Zuul's SimpleHostRoutingFilter and SendResponseFilter to
   close the underlying socket when an error occurs when writing the response.
   I hope that the code can be removen when my PR gets merged.
   Issue https://github.com/spring-cloud/spring-cloud-netflix/pull/1372

Fixes #290

With the fix for #260 we ignored all events from child contexts which turns out
to be wrong since the "main" application context is, in case spring cloud config
is used, is a child  of the bootstrap context. So we just act on the events from
WebApplicationContexts. After they're fired up the needed port information is
available.

fixes #277

With this change the AbstractNotifier isn't specialized on status changes, but
the default behaviour for the existing notifiers isn't changed.
In addition the existing notifiers have been improved so that subclassing has
become easier.
To have existing notifiers acting on other events you need to override
shouldNotify().

fixes #270

When includeing spring-cloud-netflix-hystrix-amqp to your application it looks
like that the ApplicationReadyEvent is fired twice (from main and child
application context). So we need to take care that only the events from the
main applications are taken into account.

fixes #260

As it turns out (rather obvious) that the ThreadPools for registration and
status updating needs to be destroyed on application shutdown so that the
worker threads gets cancelled. To achieve this we simply register the
ThreadPools as spring beans (since they are implementing DisposableBean).

fixes #253

When having registered some applications via discovery and some via http you
can now add the appication names of the non-discovery to the ignored services
so that they won't considered as stale an be removed from the registry by the
ApplicationDiscoveryListener.

fixes #244

With this commit you can specify the management.port for a discovered service
via the metadatamap.

Sometimes Eureka only provides only the securedhealthUrl for the service.
Previous to this commit the applciation won't be registered in that case. So
with this commit the securedHealthUrl from Eureka is used, when available

fixes #224

Checks the DiscoveryClient's services on each heartbeat and removes all
services, which are no longer registered.

Use the metadata for health-/managament-url in the default service conversion.
This allows custom health- and management-path per application.

fixes #205

fixes #205